COMMONWEALTH OF AUSTRALIA

Department of Health

SERVICE PUBLICATION No. 32.

THE HISTORY OF

PLAGUE

IN AUSTRALIA

1900—1925

Æv

J. H. L. CUMPSTON, m.d., d.p.h

Director-General of Health and Director of Quarantine,

AND

F McCALLUM, m.b., b.s., d.p.h., d.t.m. & h.

Quarantine Officer,

Commonwealth Department of Health.

ISSUED UNDER THE AUTHORITY OF THE MINISTER FOR HEALTH

1926

By Authority:

H. J. OREEN. 90VERNMENT PRINTER. MELBOURNE.

U.5769.


Sfc

üïSpAocjCjf Cut /Hop

Mi:}oimos83


COMMONWEALTH OF AUSTRALIA

Department of Health

SERVICE PUBLICATION No. 32.

THE HISTORY OF

PLAGUE

IN AUSTRALIA

1900—1925

tBy

J. H. L. CUMPSTON, m.d., d.p.h.,

Director-General of Health and Director of Quarantine,

AND

F McCALLUM, m.b., b.s., d.p.h., d.t.m. & h.

Quarantine Officer,

Commonwealth Department of Health.

ISSUED UNDER THE AUTHORITY OF THE MINISTER FOR HEALTH

1926

By Authority:

H. J. GREEN, GOVERNMENT PRINTER. MELBOURNE.

C.5760.


PREFACE.

The records of plague incidence and of activities directed against plague are scattered through a large number of official records and current journals. Some of the facts have never hitherto been published. It has seemed desirable to collect all the available information and compile it as a consecutive statement for the benefit of future students of the subject, and also for the preservation of some material which otherwise would be permanently lost. Some features, easily perceptible, are not without importance in relation to the administrative control of plague in Australia. Acknowledgement of the source of information has not invariably been made throughout this work, but, by the compilation of a comprehensive bibliography, an endeavour has been made to rectify any such omission.

J. H. L. CUMPSTON, M.D., D.P.H.

Director-General of Health.

TABLE OF CONTENTS.

PAGF!

Introduction . .    ..    . .    ..    ..    . .    . .    . .    9

PART I.—PLAGUE IN AUSTRALIA, 1900-1909.

Chapter I.—The First Introduction of Plague into Australia . .    ..    ..13

Chapter II.—Plague in New South Wales, 1900-1909..    ..    ..    .. 16

The first outbreak 1900—The second outbreak 1901-2—The Newcastle case—The third outbreak 1903—The fourth outbreak 1904—The fifth outbreak 1905—In Sydney—Extra-metropolitan outbreaks—Ulmarra— Ballina—Lismore—Newcastle—The sixth outbreak 1906—The seventh outbreak 1907—In Sydney—At Kempsey—Cases in 1908—Cases in 1909.

Chapter III.—Plague in Queensland, 1900-1909    . .    ..    ..    . .    25

Origin of the epidemic—In 1900—-In 1901—-In 1902—In 1903—In 1904—

In 1905—In 1906—In 1907—In 1908—In 1909

Chapter IV.—Plague in South Australia . .    . .    . .    . .    . .    31

In 1900—In 1909.

Chapter V.—Plague in Victoria . .    ..    . .    .    . .    34

In 1900—In 1902—In 1907—Tabular list of cases.

Chapter VI.—Plague in Western Australia . .    ..    . .    . .    . .    35

Introduction of the disease—Association with other epidemic centres— Course of the Epidemic, 1900-1906—Monthly distribution of cases—


Reported case at Geraldton, 1909.

Chapter VII.—Immunity of Tasmania . .    ..    . .    . .    . .    39

Chapter VIII.—The Course of Plague in Australia, 1900-1909 . .    . .    ..    41

Chapter IX.—Epizootic Plague in Australia    . .    . .    . .    . .    45

Chapter X.—The Epizootic in New South Wales    . .    . .    . .    . .    46

In Sydney 1900 1908—In Extra-metropolitan Districts 1902—Newcastle—

In 1905—Ulmarra—Ballina—South Woodburn—Lismore—Newcastle— Origin of the epizootic infection at Newcastle—In 1907, Ivempsey.

Chapter XI.—Epizootic Plague in Queensland    . .    . .    . .    ..    61

In Brisbane 1900-1909—In Extra-metropolitan Districts—Rockhampton 1900-1906—Townsville    1900-1907—Cairns    1900-1908—Bundaberg

1902-1905—Childers 1905—Maryborough 1904-1905—Ipswich 1900-1907—

Port Douglas 1907—Mackay 1909.

Chapter XII.—Epizootic Plague in Victoria    . .    ..    . .    ..    66

Chapter XIII.—Epizootic Plague in South Australia    . .    . .    ..    6"

Chapter XIV.—Epizootic Plague in Western Australia    . .    . .    . .    6 '

Chapter XV.—Epizootic Plague in Tasmania    . .    . .    . .    . .    7i

Chapter XVI.—Plague on Shipboard. 1900-1909    . .    . .    .    . .    7

Chapter XVII.—The Relationship between Epizootic and Epidemic Plague ..    8

Time relationship—Interval between commencement of epizootic and epidemic—Epizootic periodicity amongst different rat species—Effect of period of pregnancy on numbers of rodent population—Place relationship.

Table of Contents—continued.

I'AQH


Chapter XVIII.—Some Difficulties of Plague Investigation ..    ..    ..    95

Difficulties in tracing sources of human infection—In establishing the presence of rodent plague—Where plague rats are most commonly found—

The interval between epizootics and the “ bridge ” which connects them.

Chapter XIX.—Rat Destruction ..    ..    ..    ..    ..    .. 101

Chapter XX.—Species of Rats which are naturally found plague-infected    ..    102

Chapter XXI.—Species of Fleas concerned in Plague Transmission ..    ..    106

Chapter XXII.—Influence of Season on the Occurrence of Plague ..    ..    108

PART H.—THE INTER-EPIDEMIC PERIOD, 1910-1920.

Chapter XXIII.—Measures against the Introduction of Plague, 1910-1920    .. 113

Development of the Federal Quarantine System—Measures to prevent introduction of plague—Control of rodents on vessels—Control of rodents on shore—Notification of cases of plague on shore.

Chapter XXIV.—Plague on Vessels in Australia, 1910-1920 ..    ..    .. 123

Chapter XXV.—Plague in Oversea Countries, 1910-1920    ..    ..    .. 131

PART HI —PLAGUE IN AUSTRALIA, 1921-1922.

Chapter XXVI.—Commencement of the Epidemic ..    ..    ..    ..133

Early infection of Brisbane, Sydney, and Queensland ports—Origin of the infection.

Chapter XXVII.—The Spread within    the City of Brisbane    ..    ..    ..    139

Chapter XXVIII.—Plague at Townsville    ..    ..    ..    ..    ..    149

Chapter XXIX.—Plague at Cairns    ..    ..    ..    ..    ..    153

Chapter XXX.—Plague in other Places in Queensland    ..    ..    ..    155

Port Douglas—Ipswich—Rockhampton—Mackay—Bundaberg—Aramac —Maryborough—Toowoomba—Innisfail—Ingham.

Chapter XXXI.—Plague in Sydney    ..    ..    ..    ..    ..    157

Chapter XXXII.—The Introduction of Plague into Sydney    ..    ..    ..    181

Chapter XXXIII.—Immunity of other Parts of Australia    ..    ..    ..    184

Chapter XXXIV.—Plague on Shipboard, 1921-1922..    ..    ..    ..    185

Vessels infected with plague—Suspected plague on vessels.

Chapter XXXV.—-Some Epidemiological Features of the 1921-1922 Outbreak .. 191 Infection and prevalence of rat species in Australian ports—Distribution of flea species—Species of fleas on particular rodent species—Meteorological data 1921-1922—Persistence of infection on premises as determined by the use of sentinel guinea-pigs—Persistence of infection in localized areas in Brisbane.

Chapter XXXVI —The Spread of Plague in Australia    ..    ..    .. 203

Plague spreads only by sea routes—Migration of rodents by rail—Rapidity of spread from initial focus—Individual infected rodent not important as a passenger on shipboard except as initial focus for ship epizootic.

Chapter XXXVII.—Fumigation ofVessels .    . .    . .    ..    206

Table of Contents—continued.

PART IV. THE PERIOD 1923-1925.

PAGE

Chapter XXXVIII.—Records of the period 1923-1925    . .    . .    . . 209

Sporadic ease of plague at Sydney, dune, 1923 Case of plague, subsequently shown negative, reported from Brisbane, June, 1925—Quarantine of vessels for plague.

APPENDICES.

Appendix A.—The Intercolonial Plague Conference of Melbourne, 1G00    ..    214

Appendix B.—The Commonwealth and States Conference on Plague, 1921    ..    217

Appendix C.—Epidemiological Records required during a Plague Outbreak    ..    227

Appendix D.—Plague in Australia, Bibliographical Index . .    ..    . . 230

ILLUSTRATIONS.

Eig. ].—Map of Australia, showing principal features of Quarantine

Administration    . .    . .    . .    . .    . . Frontispiece.

Eig. 2.—Diagram of the course of plague in Australia, 1900-1910    . .    40

Eig. 3.—Map of Australia, showing localities in which plague occurred,

1900-1909    ..    ..    ..    ..    ..    ..    42

Fig. 4.—Localities in which plague occurred in Australia in each year,

1900-1909    ..    ..    ..    ..    ..    ..    43

Fig. 5.—Sketch map of Northern Rivers District, New South Wales    ..    55

Eig. 6.—Graph showing the course of Human and Rodent Plague in

Sydney, 1903-1910    ..    ..    ..    ..    ..    85

Eig. 7.—Graph showing the course of Human and Rodent Plague in

Brisbane, 1900-1907    ..    ..    ..    . .    ..    86

Eig. 8.— Graph showing the course of Rodent Plague in Sydney, 1903-1907    89

Fig. 9.—Map of portion of Sydney and suburbs showing areas affected

during the 1921-1922 plague outbreak ..    ..    ..    159

Eig. 10.—Map of Australia showing localities where plague occurred,

1921-1922    ..    ..    ..    ..    ..    ..    203

Eig. 11.—Map of Brisbane showing localities where infected rodents were

found up to 18th September, 1921    ..    ..    .. Face p. 204

Fig. 12.—Map of Brisbane showing localities where infected rodents were

found up to 24th September, 1921    ..    . .    . . Face p. 204

INTRODUCTORY.

As of importance in regard to the introduction of plague into Australia and as indicating the development of knowledge concerning the aetiology and epidemiology of plague, some of the more important dates in connexion with the present pandemic are set out in the following chronological table:—

1894.—Infection of Hong Kong probably through Canton from an endemic focus in the Chinese province of Yunnan. Bacillus pestis discovered independently by Kitasato and Yersin in Hong Kong. Association of epidemic and epizootic observed by Yersin and Lawson in Hong Kong (previously noted by Planck in India (1876) and other observers) and possibly referred to in the Bible (First Samuel, Chapters IV., V., and VI.).

1896. —Infection of Bombay, Osaka, and Formosa. Haffkine -(Bombay) developed anti-plague serum.

1897. —International Conference on Plague at Venice. Ogata (Japan) suggested suctorial insects as vectors from rat to man. Association of epidemic and epizootic observed by Snow, Weir, Hankin, and Simond in India.

1898. —Infection of Madagascar and Jeddah. First Plague Commission of India appointed. Simond (France) reported observations on the role of tleas as vectors from rat to man.

1899. —Infection spread to Malay States, Philippine Islands, Japan, New Caledonia, the Sandwich Islands, San Francisco, Asuncion, Ilosario, Buenos Ayres, Rio de Janeiro, Oporto., Lisbon, Alexandria, further Red Sea ports, French Ivory Coast, Persian Gulf, and Mauritius. German Plague Commission appointed.

1900. —Infection spread to Australia, Cape Town, and Glasgow. Plague present in every quarter of the Globe'—Europe, Asia, Africa, North and South America, and Australasia.

1903. —Infection of Peru. International Sanitary Conference of Paris.

1904. —Infection of Johannesburg, South Africa. Appointment of an Advisory Committee of the India Office, Royal Society, and Lister Institute to investigate plague.

1905. —Infection of Persia and Russia.

1906. —Infection of Leith (Scotland) and Guayaquil (Ecuador).

1908.—Infection of Shanghai.

1907.—Infection of Accra (Gold Coast). Appointment of second

Plague Commission of India.

1910. —Infection of Soerabaya (East Java). Pneumonic plague

epidemic in Manchuria.

1911. —Spread of infection inland in East Java.

1914.—Infection of Colombo (Ceylon).

1916. —Infection of Semarang (Mid-Java).

1917. —Extension of infection in Mid-Java.

1920-21.—Pneumonic plague epidemic in Manchuria.

Plague in Australia.

Any discussion of the history of plague in Australia falls naturally into consideration of five periods :—

(1)    Prior to the introduction of plague;

(2)    The outbreaks of 1900-1909;

(3)    The plague-free years of 1910-1920;

(4)    The outbreaks of 1921-1922;

(5)    The years 1923-1925.

With regard to the period prior to the discovery of plague in Sydney in 1900, during the pandemic extension of that time, there is nothing to indicate that infection had ever appeared in Australia. It is interesting to note, however, that in a “ Table of Deaths for Hobart Town for the Years 1842, 1843, 1852, 1853,” appended to a paper on “ Tne Epidemics of 1852-3 ” (Proceedings of Koyal Society of Van Diemen’s Land, Vol. II., Part III., January, 1854), Dr. E. S. P. Bedford records a death from plague in November, 1843. It is now obviously impossible to interpret this entry, in view of the loose use of the term “ plague ”, even at the present time.

In giving evidence before the Select Committee that inquired into the quarantine laws at Sydney in 1853, Dr. H. G. Allevne, the Port Health Officer, stated: “We are not at present threatened with the importation of yellow fever, plague, or cholera, against which quarantine is established in other countries.”'—(H.S.W. Votes and Proceedings, 1853, Vol. II.)

At the time of the origin of the pandemic wave that spread over the world following the year 1896, it may be noted that the leading health authorities in Australia were fully conversant with the world movements of the pandemic, with the resolutions of the Venice Plague Conference of 1897, on which the control measures then in force were based, and with the significance of the association of epidemic with epizootic which was then being recognized by sanitary officers in the Far East and India.

In Victoria in 1898 a proposal was mooted to send a medical man to study bubonic plague in India at first hand, but, failing Government support, the project fell through.

The declaration of Noumea as plague-infected in December, 1899, resulted in the adoption of intensive rat-destruction measures on vessels arriving in Sydney from that port (see page 15). The role of the flea in the transmission of plague had been indicated by the work of Ogata (1897), of Japan, and Simond (1898), of France, and the observations of the latter were noted by Ashburton Thompson in his 1900 Plague Report as having furnished a guide for epidemiological and laboratory investigation on the first appearance of plague in Australia. This early recognition by the authorities of the factors concerned in the transmission of plague, and the enthusiasm of sanitary officers throughout Australia, led to a gradual confirmation and extension of knowledge throughout the 1900-1909 series of outbreaks. The detailed records of Ashburton Thompson and Tidswell at Sydney, and of Burnett Ham at Brisbane, now rank amongst the classical literature of the world on the epidemiology of plague.

Macjvsar


ClHtjEA


PAPUA


Sou'.iMya’

JAVA


Koep»>


770«


300m


Port

»*or ti#jr


Wodlirk I


ÂOtQnà ISflfi*


Thursday


Island


SJIOM.1N

I31ANCS


Darwin


Katherine


Wyndham


aims


%Derby X

Broome


foisayth


PònrjuwMi 'O


Townsville


Cloncurr^


Port Hedland


Cossack


Mackay


OasIovv


tongrearf.


Rockhampton


Gladstone


Charieviiie


Bundabprg\

Maryborough


Meaeetharr*


0Ooflnadntta


I50HJTi


Cuonanultu


BHISBANE


Mungñfji


herald top


KalQooHie


FKKMANTLK


Streaky Bay


Auqu.sta


broken Mil


Hunbiiry


Wallaroo


Port Pirie


ronjotioli


Newcastli


HoT

iTAj^ra'

'plOidHowe


rOOO^L


fyrifVXL


SYDNEY


tOäOm


Albany


CO \Pòri Victor


Port Kembla


576001


Portland


COMMONWEALTH OF AUSTRALIA

showing principal features of Quarantine administration


rMQts-


Major Quarantine Stations shown thus H Principal Trade Routes From oversea Mmor “    "    m    to First port oF entry, shown thus

Prior pot existing Rb/lway liner,    -----Routes and distances on Coast    *

" proposed "    "    •*    ................. Ports oF entry underlined

Ports other than Ports of entry at which Quarantine Officers are stationed marked with cross


TASMANIA


Launcoston


'Omm


S70m


Hobart


JÏT-,rl2Cit2 rrn •»>


PART I.

CHAPTER I.—THE FIRST INTRODUCTION OF PLAGUE INTO

AUSTRALIA.

The definite history of plague in Australia commenced on 19th January, 1900, when a carman, regularly employed in carrying goods from city warehouses in Sydney to Central Wharf, Sydney, fell ill with a disease, subsequently diagnosed to be the bubonic form of plague.

On 15th January, 1900, certain cases had occurred at Adelaide which were considered to be plague. These are discussed later (vide page 31); but, as Thompson says, “the rumour, which from the first has been regarded with doubt, was ultimately discredited.”

The source from which the disease entered Australia was never accurately determined. As shown in the introduction, the overseas centres of infection were, at this date, very numerous, and included many countries with which Australia Avas in constant maritime communication. The danger of importation of plague by sea into Australia had never been absent from May, 1894, at which time plague had been officially declared to be epidemic at Hong Kong, and this danger had increased pari passu with the establishment of the disease in epidemic form at other ports in communication with Australia.

During 1899, Mauritius (February), Japan (December), Honolulu (December), and New Caledonia (December) had all become definitely infected with plague.

Thompson’s conclusion as to introduction is contained in the following :—Beyond pointing out the several ports from which plague might have been introduced into Sydney, and the great number of vessels which arrive from those ports during each year, nothing can be said as to the way in which the disease actually was introduced.’’—(1900 P.R., p. 22) 1. As to the precise mode of introduction, Thompson is more definite. He expresses “ an opinion that the disease was not introduced, either by some unobserved imported case in man, or by importation of infected articles, but by infected rats, from which it spread to the local rats . . . ; but by what vessel, or from which infected port, such rats Avere landed at Sydney, there is no evidence.” — (1900 P.R., p. 23.)

Notwithstanding this expressed uncertainty as to the overseas source of infection, it appears likely from Thompson’s remarks that lie held

strongly the suspicion or conviction that the disease had been introduced from New Caledonia :—■

“ The first case in man must have happened in New Caledonia some time before the presence of plague was acknowledged on 24th December (1899); and it may have happened considerably before that date. But appearance of the disease among rats, not among the inhabitants, has most interest in relation to the risk of importing the infection. Now, it was reported that the rats at Noumea suffered heavily during the epidemic ; but the important question whether the epizootic preceded the epidemic cannot at present be positively answered, no authoritative information on this point having become available. A frequent experience, however, is that rats suffer first, and usually several weeks before appearance of the first case in man. If this happened at Noumea, there was nothing to prevent importation thence at any time prior to 24th December, for no special precautions were or could be taken at Sydney until after that date, when the disease was first officially admitted to be present there in man.”—(1900 P.R., p. 23.)

At the International Medical Congress of Berlin, in 1907, Thompson stated :—“ Australia escaped invasion by plague until after the disease had appeared at the capital of New Caledonia, an island which lies 1,000 miles from Sydney, in the fourth quarter of 1899. The infection entered by way of Sydney, where attack in the first case occurred on 19th January, 1900.”—{Cong. Trans., Vol. VII., p. 672.)

Tidswell states:—“We did not succeed in discovering how the rats first became affected. The Port of Sydney is in frequent communication with infected places in China and India, and also with the Sandwich Island and Noumea, where plague was prevalent at the time of our outbreak. But there was no evidence that any contaminated article or plague rats reached our shores from any of these places. The only fact bearing upon the point is that, amongst the rats forwarded to the laboratory for examination there was a large rough black-coated rat, different from the local rats, and said to be an Indian species. This particular specimen was perfectly healthy. .    .    . We did not

succeed in gleaning even a suspicion that any person sick with plague had come to the Colony from abroad.”—(Journal of the Royal Sanitary Institute, Vol. XXI., Part IV., pp. 563, 569.)

The French authorities have adopted an unequivocal attitude:—

“ La peste fut importée d’Australia en 1899. Elle persista en 1900 au chef-lieu et reapparut en 1901. En 1902-1903, divers points de la brousse furent envahis. En 1899-1900, 124 cas furent constates a Noumea et dans la brousse, dont 45 Européens, avec 59 deces sur les 79 cas indigènes et 21 décès chez les Européens.— (Chant emesse et Mosny Traite (THygiene, Vol. XI., Hygiene Coloniale, p. 504.)

In connexion with this controversy, some interest attaches to the fact that the first patient was a carter, whose daily work took him continuously to the Central Wharf during 25 days before his attack, and between 21st October, 1899, and 20th January, 1900, four vessels which had touched at Hong Kong lay at Central Wharf—one of them from 9th January to 20th January.— (P.R., 1900, p. 22.)

After the declaration of Noumea as plague infected, attempts were made to kill any rat which might still remain on these vessels, notwithstanding the efforts to the same end which had usually been made at the port of departure; and sometimes these measures yielded a considerable number of dead rats—in one case, as many as 283. It does not, however, appear that similar measures were taken before the declaration of Noumea.—(P.R., 1900, p. 14.)

The first mortality among rats had occurred at wharfs adjacent to the Central Wharf above-mentioned, and during the first week in January. After the first human case, the next four cases all were undoubtedly infected within a small area round these particular wharfs.

The circumstances associated with the beginning of plague in Australia direct attention to—

(1)    the long latent period, 1894-1899, during which plague was

spreading only slowly in the Far East; this period being followed by

(2)    the appearance of plague in Australia concurrently with a

rapid world-wide spread of the disease—new appearances being recorded from widely-separated countries within a few months;

(3)    the uncertainty as to the overseas source of infection;

(4)    the absence of any indication of danger which might have

been afforded by the presence on arriving vessels of human cases of the disease;

(5)    the international transfer of infection by means of rats;

, (6) the absence of any measures to prevent importation of infection by rats from overseas.

CHAPTER II—PLAGUE IN NEW SOUTH WALES.

The First New South Wales Epidemic.

The first case recorded in New South Wales was that of the carter mentioned in the previous chapter, whose illness first declared itself on 19th January, 1900.

Thereafter the course of the epidemic may be followed in the table hereunder:—

Table 1.

Numbers of Attacks and Deaths Recorded During Each Week.

1900.

Week Endinsr.

Cases.

Deaths.

Jan. 20 . . . .

1

0

27 . . . .

0

0

Feb. 3 .

0

0

10 . . .

0

0

17 .. ..

0

0

24 . . .

2

1

March 3 .

2

1

10 . . ..

5

3

17 .. .

12

3

24 . . .

10

3

31 . . .

23

6

April 7 . . .

29

9

14 . . .

29

12

21 .. ..

16

8

28 . . .

26

7

May 5 . . ..

38

10

12 .. ..

23

10

19 . . .

24

10

26 . . .

7

6

June 2 .

17

3

9 . . .

4

3

16 . . .

10

3

23 . . . .

6

0

30 . . .

12

3

July 7 .. .

1

0

' 14 . . .

3

0

21 . . .

2

0

28 . . . .

0

1

Aug. 4 .

0

0

11 .. ..

1

0

18 . . .

0

1

i_________

Totals .

303

103

The Second New South Wales Epidemic.

The last case of the epidemic of 1900 was notified on 9th August of that year. “ An interval of rather more than fifteen months ensued, during which careful watch was kept for the commencement of the recurrence which was feared; but among the many cases which were reported for diagnosis during its continuance, there were but two which afforded good ground for prima facie suspicion, and after investigation it was shown that both were due to streptococcic infection. The rats which infested the areas on which cases had arisen were also watched until it appeared probable that the epizootic of plague which had prevailed among them had died out.” The long interval was ended by the

-attack of a man on 1th November, 1901; his case was notified on 12th November. A free term of 31 days ensued, and then, on 8tli December, a second man was attacked. After a further free term of about 35 days, a woman fell ill on lOtli or lltli January, 1902. During these two intermissions several cases of illness were reported for diagnosis, but no case of plague, nor any in which there was real ground for doubt, was among them. The epidemic declared itself with the third case, and, as the last patient was attacked on 8tli June, it may he referred to conveniently as the epidemic of 1902. It consisted of 139 cases, of which 39 ended fatally. The sequence of the cases is shown in the table hereunder:—

Table 2.

Numbers of Attacks and Deaths Recorded During Each Week,

1901-1902.

Attacks.

Deaths.

1901.

November 9

1

0

lb

O

0

29

0

0

30

0

0

December 7 . .

0

0

14

1

1

21

0

0

28

0

0

1902.

January 1 .

0

0

1 1 .

1

0

18 .

2

0

25 .

3

1

February 1 .

0

0

8 .

5

2

15 .

9

4

22 .

12

5

March 1 .

14

4

8 . .

5

O

15 .

12

5

22 . .

18

.3

29 .

8

1

April 5 .

5

0

12 .

1

O

19 .

b

1

2b .

8

2

May 3 ..

5

.3

10 ..

b

1

17 .. 24 .

7

2

3

1

.31 . .

2

O

June 7 ..

5

2

14 .

1

0

1.39

39

The Newcastle Case.—On 6tli August, however, one further case occurred at Newcastle. It was “indigenous” to that city, and was not followed by other cases. (E.R. 1902 p. 3.)

The Third New South Wales Epidemic.

The date of attack in the last case of the 1901-1902 outbreak was 8th June, 1902; the last plague rat Avas taken on 14th July, 1902. The 1903 outbreak began in an epizootic of plague of which the first evidence was got on 12th May, 1903, and the last on 15th August, 1903. It consisted, on the human side, of two cases of plague in man; in one of which the date of attack was 17th June, and in the other of which the date of attack was 2nd July; both of these persons recovered. It will be necessary at a later stage to consider the course of this epizootic, but for present purposes the human cases are recorded in the following •—

Table 3.

Numbers of Attacks and Deaths in the Third Epidemic, 1903.

Attar: ks.

Deaths.

June 17

1

0

July 27 ..

1

0

Totals

2

0

The Fourth New South Wales Epidemic.

The last evidence of presence of plague in Sydney connected with the preceding outbreak was got on 15th August, 1903, when the infection was identified in the carcase of a rat. The outbreak of 1904 consisted in an epizootic of plague of which the first direct evidence was got on 1st March, 1904, the last on 3rd December; thus it continued during nine months. Its course was marked by the occurrence of plague in twelve persons who inhabited eleven dwellings, of whom six died; the first case was notified 9th March, the last on 10th September, 1904, and these dates defined a period of a little over six months, which fell within the time limits of the epizootic. The following table shows the dates on which the twelve cases occurred:—

Table 4.

Numbers of Attacks and Deaths in the Fourth Epidemic, 1904.

Attacks.

Deaths.

March 9 . . ..

1

0

April 10 .. . .

1

0

20 .. . .

1

0

22 .. . .

1

0

25 . . . .

1

1

May 8 .. . .

1

0

25 .. . .

1

0

31 .. . .

1

1

June 19 .. . .

1

1

July 31 . . . .

1

1

Sept. 7 .. . .

1

1

10 .. ..

1

1

Totals ..

12

6

The Fifth New South Wales Epidemic.

Epidemic in Sydney.—Although the sequence of cases in Sydney in 1905 is called by Thompson the “ fifth outbreak of plague in Sydney,” it cannot be considered otherwise than as continuous with the outbreak of 1904. The last case in 1904 had occurred on 10th September, and the last plague rat had been identified on 3rd December. The continuous examination of rats, which began with the outbreak of 1901-2, haying been maintained steadily since then, the first plague rat in 1905 was identified on 18th January. The date of attack in the first case of 1905 was 11th March, and in the last case of that year it was 12th July. The last plague rat was identified on 5th December. The number of cases was eighteen, of which five were fatal. The following table shows the sequence of cases in Sydney during the year 1905 .

Table 5.

Numbebs of Attacks and Deaths in the “ Fifth Outbbeak."

Attacks.

"Deaths.

March 11 .. ..

1

0

24 .. ..

1

1

April 2 .. ..

1

0

3 .. ..

1

O

6 .. ..

1

0

10 .. ..

1

1

13 .. ..

1

0

15 . . ..

1

0

20 .. ..

1

0

23 .. ..

1

0

24 .. ..

1

0

26 .. ..

1

0

Mav 5 .. ..

1

0

13 .. ..

1

0

15 .. ..

1

0

23 .. ..

1

1

June 27 .. ..

1

1

July 14 .. ..

1

1

Totals .

18

5

Extra-Metropolitan Epidemic in New South Wales.—The year 1905 is notable for the fact that, although plague had been present in Sydney since the beginning of 1900, there had been no record of plague in either epizootic or epidemic form outside of the metropolis until that year. To this statement an exception must be made of the single case which occurred at Newcastle in 1902. As this was an isolated case, it does not affect the general statement here made. The outbreaks in that year in New South Wales outside of the metropolitan area were as follow:—

1.    An epidemic at Ulmarra, on the Clarence River.

2.    An epizootic at Woolgoolga.

3.    An epidemic at Ballina, on the Richmond River.

4.    An epizootic at South Woodburn, on the Richmond River.

5.    An epidemic at Lismore, on the Richmond River.

6.    An epidemic at Newcastle.

The Epidemic at Ulmarra.—This epidemic extended over the period 14th December, 1904, to 6th May, 1905, the attack dates of the thirteen cases being as follows:

-—-

Cnpes.

Deaths.

1904.

Deo. 14 .. ..

i

1

29 .. ..

2

1

30 .. ..

2

1

1905.

•Jan. 1 . . . .

1

I

21 . . ..

1

O

22 .. .. .)o

1

1

0

1

».) . . .. 20 . . . .

1

2

1

1

27 .

i

1

May 6 .. ..

i

1

Totals .

13

8

The Epidemic at Baltina.—This epidemic comprised four cases in all, the attack dates being as follows

- -

Cases.

Deaths.

1905.

Feb. 3 . .

1

1

April 22 ..

1

1

May 2 ..

1

1

28 ..

1

0

Totals

4

3

The Epidemic at Lismore.—Millard, in describing this outbreak, indicates the possibility of certain unrecorded cases of plague preceding the officially controlled epidemic—

“ The first recognized case of plague at Lismore was attacked on 1st May, 1905. It is not, however, certain that this was the first case that occurred. Three deaths, one in March, and two in April, had been certified as due to dengue fever. This disease is seldom fatal, and, in discussing these cases with their medical attendants, I learned that their symptoms were not typical of dengue, and that, in the light of subsequent occurrences, plague could not be absolutely excluded. At the same time, however, there was widespread epidemic of dengue in Brisbane, and several other cases are said to have occurred in Lismore.” (P.B., 1905, p. 35.)

The recorded epidemic included eight cases which occurred as follows:—

--

Attar Us.

Death?.

1905.

May 1 •

2

1

' 3 ■

l

0

7 .

2

2

9 .

l

0

11 .

1

0

30 .

1

0

Totals .

8

3

Epidemic in the City of Ncw castle.—Subsequent to the notification of the single case on 6th August, 1902, no further case of plague was reported at Newcastle until 25th March, 1905. Following on this case was a series of fourteen cases, which comprised the Newcastle epidemic of 1905. These cases occurred as follow:—

Attarks.

Deaths.

1905.

March 22 .. ..

1

0

25 .. ..

1

1

28 .. ..

1

0

31 .. ..

1

0

April 22 .. ..

l

1

27 .. ..

1

0

May 3 .. ..

1

|

1

n

11 .. ..

1

0

19 .. ..

1

0

20 .. ..

1

0

29 .. ..

l

0

30 .. ..

1

0

July 2 .. ..

1

0

Totals ..

14

3

The Sixth New South Wales Epidemic,

The sixth epidemic of plague in New South Wales was limited to the metropolitan area of Sydney.

“Attack occurred on 12th July in the last case of plague in 1905, and the last plague rat in 1905 was identified on 5th December. In 1906 the first plague rat was identified on 23rd January. Attack occurred in the first case in man on 12th March, 1906, in the last on 22nd December, 1906; and the last plague rat was identified on 29th December, 1906. The total number of cases was 20, of which eight were fatal.” (P.R., 1906, p. 1.)

The sequence of cases in this outbreak is shown in the following table:—

Table 6.

Number of Attacks and Deaths in the “Sixth Outbreak."

Attacks.

Deaths.

1906.

March 9 ..

2

0

10 ..

2

0

12 ..

2

0

16 .. . .

1

0

May 11 ..

1

1

June 5 ..

1

1

17 .. .

1

1

20 ..

1

1

23 ..

2

0

26 . .

1

* ) Pneumonic cases

2S .. . .

1

1 j (P.R., 1906, p. 7)*

July 3 ..

1

0

10 .. ..

1

1

14 ..

1

0

Oct. 1 .. .. :

1 s

1

Dec. 22 .. ..

1

0

Totals

20

8

* This was the only occurrence of pneumonic plague recorded in New South Wales.

The Seventh New South Wales Epidemic.

The seventh epidemic of plague in New South Wales aifected two distinct localities—the metropolitan district of Sydney, and the northern country centre of Kempsey, on the Macleay Kiver.

The Epidemic in Sydney.—In 1906 attack occurred in the last case -on 22nd December, and the last plague-rat was taken on 29th December. In the year under review, attack occurred in the first case on 7th January, 1907; the first rat in -which plague was identified was taken on 10th January, the last on 21st September. Attack in the last case occurred on 29th December, 1907; but plague-rats in number were discovered in connexion with it, and with another which preceded it (attacked 27th December) as soon as search had proceeded sufficiently, namely, on 2nd January, 1908 [P.R. 1907, p. lj. Forty-seven cases occurred during 1907, of which 16 ended fatally.

The sequence of eases during this outbreak was as follows -

Attacks and Deaths Recorded During 1907.

Table 7.

Attacks.

Deaths.

1907.

Jan. 7. . ..

1

9. . ..

1

1

15.. ..

1

1

17.. ..

1

18.. ..

1

21.. ..

1

1

22.. ..

1

23.. ..

1

24.. ..

1

1

25.. ..

2

26.. ..

3

1

Feb. 5.. ..

1

6.. ..

2

1

9.. ..

2

10.. ..

1

12.. ..

1

1

13.. ..

1

. .

14.. ..

1 •

• • *

15.. ..

1

1

16.. ..

2

1

20.. ..

1

21.. ..

1

March 1.. ..

1

3.. . .

1

4. . ..

1

1

7.. ..

1

9.. ..

1

15.. ..

1

16.. ..

1

18.. ..

1

1

21.. ..

1

1

22.. ..

1

1

April 7.. . .

1

8.. . .

1

1

9.. ..

1

13.. ..

1

1

14.. ..

1

May 5.. ..

1

1

19.. ..

1

Dec. 28.. ..

1

29.. ..

1

Totals ..

47

16

The Epidemic at Kempsey.—At this country town the outbreak was limited to four human cases which occurred in the following sequence:—

Attacks.

Deaths.

1907.

Jan. 23.. .

1

1

29.. ..

1

1

Feb. 1.. ..

1

1

6..

1

1

Totals . .

4

4

1908.

During 1908 there were six cases, all in the metropolitan area. Details of these cases are as follow:—

Attacks.

Deaths.

1908.

Jcan. 8 . . . .

1

..

Feb. 24 . . .

1

. •

Mtarch 29 . . . .

1

1

Mcay 4 . . ..

1

1

9 . . . .

1

1

June 24 . . . .

1

1909.

During 1909, 23 cases occurred-—twenty of which were in the metropolitan area; two were members of the crew of the steamer St. Louis; and one case occurred at Newcastle; this latter case (a ratcatcher) was infected at Sydney, and developed the disease at Newcastle. -It is therefore proper to include this case amongst the metropolitan cases, making a total of 21.

The following table shows the sequence of cases in Sydney during 1909, the dates given being the date of onset of the disease:—

Table 8.

Number of Attacks and Deaths, Sydney, 1909.

Attacks.

Deaths.

1909.

March 0 .. . .

•)

1

12 . . . . l

1

1

1

1

i«i .. . .

15 .. ..

1

20 . . . .

1

22 . . ..

2

April .1 . . ..

i

1

5 . . . . 7 . . . . 10 .. ..

•>

•>

:i

l

lVf . . ..

May 7 . . . .

1

l

8 .. . .

l

1

V*

13 .. ..

l

l

1

Totals ..

21

0

* Date of notification, 28.5.09.

The case on 13th May, 1909, was the last case which occurred in New South Wales. Human plague disappeared totally until 1921.

CHAPTER III.—PLAGUE IN QUEENSLAND.

Origin of the Epidemic.

The origin of the outbreak in Queensland is ascribed by Ham to the importation of infection, conveyed through the agency of rats, from vessels arriving at Queensland ports from Sydney at a time when plague was known to exist at the latter place. On 19th January, 1900, plague was reported to have broken out at Sydney, and it was subsequently ascertained that rats had been dying upon one of the wharves at that town about the first week in January, 1900. On 14th February, seven plague-infected rats were obtained from one Sydney wharf. In view of the close and constant commercial communication between Sydney and Brisbane, the health authorities at Brisbane were on the alert and inaugurated a crusade of rat destruction combined with bacteriological examination of all rats found sick or dead. On 5th March, 1900, a black rat (Mus rcittus) found dead in a shop in Brisbane, close to a wharf at which vessels from Sydney had recently arrived, was found to be infected with plague. It was not, however, till the 27th April, 1900, that a plague case occurred among human beings in Brisbane. This case was not the first case of plague in man in Queensland. On 17tli April, 1900, the head steward on board the s.s. Burwah, a coastal vessel, carrying passengers and cargo between Sydney and Rockhampton, and calling en route at Brisbane, was reported by the health officer at Rockhampton to be suffering from plague. As this patient was taken ill a day prior to the arrival of the vessel at Rockhampton, it is fair to assume that he contracted the disease either at Brisbane—where rats had been found dead of plague on the wharves since 5th March, but where no case had as yet occurred in human beings—or at Sydney, where an epizootic and an epidemic were both present at the time the vessel left on the 10th April, 1900. On removal of the lining of the cabin occupied by the patient on the s.s. Burwah, several dead rats were found. In a report dated 8tli May, Dr. Turner, the special plague medical officer at Rockhampton, stated that about a fortnight previously the head wharfinger at Rockhampton had noticed four or five dead rats lying about the wharves every morning for three consecutive days- after this he found two rats daily, the last being found five days prior to 8th May. During the same period three or four dead rats had been observed every morning in a store opposite the wharves. On 15th April, a resident of Rockhampton was attacked, and, thereafter, until 15tli June, 1900, twenty-five cases occurred in that town. Ham | Blague in Queensland, p. 3], after reviewing the evidence, concludes:

“ The above facts support the opinion that the disease was introduced by plague-infected rats from Sydney, and that the infection spread to the local rats, which in turn communicated it to man.”

Course of the Epidemic.

The course of the epidemic in Queensland is concisely outlined hereunder.

I 900.

The first plague-infected rat was found at a Brisbane wharf on 5th March, 1900. The first human case of plague 'was reported on 15th April, 1900, at Rockhampton. The first case in man in Brisbane occurred on 27th April, followed by a rapid succession of cases comprising the epidemic. The last case of plague in man was reported at Brisbane on the 13th December, 1900, the last infected rat at Brisbane on 24th October, 1900.

The following statement shows the progress of the epidemic in Queensland during the year 1900

Table 9.

Place.

Population.

Duration of Epidemic.

Cases.

Deaths.

Probable Source of Infection.

Brisbane-Metropolitan Area

125,500

27th April-13th December

56

25

Sydney

Ipswich

15,246

21st May.. ..

1

0

Brisbane

Rockhampton ..

19,691

15th April-17 th August

36

21

Sydney

Townsville .

15,506

28th April-16th September

37

9

Sydney or Rockhampton

Charters Towers

20,976

30th September . .

1

0

Townsville

Cairns

3,467

10th May-26th July

5

2

Sydney, Brisbane, or Townsville

The following table shows the monthly distribution of the human cases and of infected rats identified:—

Table 10.

Metropolitan Area.

Human cases.

Infected Rats.

January .. .

0

0

February . .

0

0

March . .

0

5

April . .

3

3

May . .

11

0

June . .

8

15

July . ..

15

21

August . .

4

24

September . .

5

15

October . .

4

7

November . .

4

0

December . .

2

0

1901.

After an interval of seventy-five days, plague again made its appearance in Brisbane, the first case in 1901 being reported on 28th February,

1901. The first infected rat in this year was found on 4th April, 1901. The last infected rat was found on 22nd November, 1901, and the date of the last human case was 9th December, 1901.

During this year no case of human plague was officially reported outside of the Brisbane area. During the year a total of 36 cases, twelve of which were fatal, was recorded. The highest number of cases reported in any one week Avas four, for the week ending 14th May,

1901.

1902.

During the year 1902, the epidemic in Brisbane ran a rapid and somewhat severe course, reaching its maximum in the month of April. By the end of May, 81 cases had been recorded, with 26 deaths. One sporadic case occurred in August after a quiescent period of over two months. Cases occurred also in ToAAmsville, Bundaberg, and Gladstone.

The following statement shows the incidence of plague in Queensland for the year 1902 :—

Table 11.

Place.

Date.

Cases.

Deaths.

Brisbane .. . .

27th January to 4th August

82

2G

Townsville . . .

20th August to 2Gth November ..

7

5

Bundaberg . .

13th October .. . ..

1

1

Gladstone .

25th August ..

1

1

1903.

This outbreak, the fourth in Queensland, consisted of 29 cases with seventeen deaths, distributed as follows:—

Table 12.

Place.

Date.

Cases.

Deaths.

Brisbane .. ..

8th February to 11th September

21

11

Bundaberg ..

t •• .. .. ..

2

1

Rockhampton ..

11th February to 21st February

2

2

Townsville ..

t........

3

2

Cairns .. ..

t......

1

1

t The dates of these eases are not now available.

1904.

The last human case of plague in Brisbane during 1903 occurred on 11th September; thereafter there was an interval until February, 1904, when plague was again reported in Brisbane. It continued to occur until 14th September, after which no further cases were reported for the year. During the year 35 cases, with twelve deaths, occurred in Queensland, the distribution being as follows:—

Table 13.

Place.

Date.

Cases.

Deaths.

Brisbane . . .

9th February to 14th September

30

8

Ipswich .

10th July . . . . .

1

1

Maryborough

3rd June to 13th June . .

2

1

Cairns

lGth February to 22nd March ..

2

2

28

1905.

The first case in Queensland in 1905 Avas reported in Brisbane on 1st January.

The distribution throughout the State for the year AA’as as follows:—

Table 14.

Place.

Date.

C'a ses.

Deaths.

Brisbane .

1st January to 14th June

28

15

Bundaberg .

3rd February

1

1

Ispwich . .

oth May to 4th July

8

2

Childers

16th May .. . . . .

1

1

Maryborough . .

19th May to 10th June . .

10

8

Cairns .

24th June . . . . ..

2

0

Townsville

4th August to 19th October

6

6

Ham (Ann. Rep., 1905, p 2), states that tAvo of the • Cairns cases AA’ere men employed in rat-catching.

The Maryborough outbreak Avas the only instance of pneumonic plague in Queensland throughout the Avliole period.

1906.

The distribution of plague cases in Queensland in 1906 AA’as as f oIIoaa’s :—■

Table 15.

Place.

Date.

Cases.

Deaths.

Brisbane . . . .

6th March to June

81 11

4Ì 7

November to 18th December

3/

3/

Rockhampton . .

3rd April to May

11

4

Cairns

July, September, October

10

1

1907.

The first human case of plague in Queensland in 1907 occurred in Brisbane on 3rd January. The first plague-infected rat had been found in the city the day before—the 2nd January, 1907.

The distribution of the plague cases in Queensland in 1907 Avas as foIIoaa^s :—■

Table 16.

Place.

Date.

Cases.

Deaths.

Brisbane

3rd January to September .

40

20

Ipswich

12th February .

1

1

23 rd May -

1

1

Port Douglas

January to May

10

2

Townsville

17th March . .

1

1

The distribution of plague cases in Queensland in 1908 was as follows:—

Table 17.

Place.

Date.

Cases.

Deaths.

Brisbane

January to 5th November

14

8

Cairns

January to June . . . .

14

7

Mackay

29th April . . . . . .

1

1

1909.

This was the last year in which human cases of plague were recorded in Queensland, two cases being recorded at Mackay, one in January and one in June, both of which were fatal. The only plague-infected rats identified in this year were five, which were found at Mackay during July, August, and September, 1909. ISTo plague-infected rats were found during this year in the metropolitan area.

Table 18.

Plague in Queensland, 1900-1909.

Locality.

moo.

1901.

1902.

1903.

1901.

1905.

1906.

1907.

1908.

1909.

Total

Cases.

Total

Deaths.

Brisbane (Metropolitan Area)—

Attacks .

56

36

82

21

30

28

11

40

14

318

. .

Deaths . .

25

12

26

11

8

15

7

20

8

132

Ipswich—

Attacks . .

1

1

8

2

12

. .

Deaths . . .

1

2

2

, ,

5

Maryborough—

Attacks . .

2

10

12

Deaths .

1

8

9

Childers—

Attacks .

1

1

. ,

Deaths ..

1

1

Bundaberg—

Attacks ..

1

2

1

4

Deaths .. . .

1

1

1

3

Gladstone—

Attacks . .

1

1

Deaths . . . .

1

1

Kockhampton—

Attacks ..

36

2

11

49

, .

Deaths .

21

2

4

27

Townsville—

Attacks ..

37

7

3

6

1

54

Deaths ..

9

5

2

6

1

23

Cairns—

Attacks ..

5

1

2

2

10

14

34

Deaths . . . .

2

1

2

1

7

13

Port Douglas—

Attacks ..

10

10

Deaths .. ..

2

2

Charters Towers—

Attacks ..

1

1

Deaths . . ..

Mackay—

Attacks ..

1

2

3

Deaths .. ..

1

2

3

Total Cases ..

136

36

91

29

35

56

32

53

29

• 2

499

219

,, Deaths . .

57

12

33

17

12

33

12

25

16

2

219

Table 19.

Monthly Distribution of Human Plague in Brisbane,. 1900-1908.

1900.

1901.

190?.

190'*.

1901.

1905.

1906.

1907.

1908.

Total

Cases.

January ..

1

4

21

4

30

February ..

. .

1

13

5

5

16

3

2

45

March ..

7

21

4

. .

2

2

3

3

42

April ..

3

7

28

6

7

1

2

4

1

59

May ..

11

12

18

4

11

4

2

4

. ,

66

June ..

8

3

# ,

, ,

1

1

2

1

2

18

July

15

3

. .

. .

• .

. •

3

. .

21

August . .

4

1

1

5

•.

1

12

Septembe r

5

..

..

2

1

1

• •

9

October ..

4

1

• •

• .

. •

..

..

..

5

November..

4

. «

. .

. .

2

. .

1

7

December

2

1

• •

• •

• •

1

• •

• •

4

Total cases

for year

56

36

82

21

30

28

11

40

14

318

1900.

The commencement of the epidemic as officially declared in South Australia was marked by a controversy between different sections of the medical profession. Three cases were reported during January, 1900, and officially recognized by the Central Board of Health. The facts are best presented by quoting from the report by the Chairman of the Board of Health, Dr. W. Ramsay Smith [Deport on Bubonic Plague at the Adelaide Hospital, 1900, p. 20] :—

“ It will be well at this stage to give a historical resume of the appearances in connexion with this outbreak of plague, so far as they are known at the present time—

1st January, 1900.—Eppstein admitted to Adelaide Hospital from Gawler; died 12th January.

5th January.—McCann admitted to Adelaide Hospital from Gawler.

10th January.—Nurse V. developed glandular swellings.

18th January.—Boy Neale, from Knox-street, city, examined by Dr. Morris at Destitute Asylum; found to be suffering from plague for some time previously.

18th January.—Nurse D. developed glandular swellings.

18th January.—Dead rat found ^at Hospital near place where Eppstein had been.

21st January.—Two more rats, one mouse, and one bird found dead at the same place.

21st January.—Boy Neale removed to Adelaide Hospital.

29th January.—Rat found dead in King William-street, examined, and found to have been suffering from plague.

It will be seen that Eppstein and McCann were admitted from the country to the Adelaide Hospital with plague on the 1st and 5th of January, respectively. On the 18th the boy Neale, in Knox-street, was found to have been suffering from a disease for some weeks, which was proved on investigation to be plague. I am not in a position to lay before you evidence regarding other cases of illness that have presented suspicious symptoms, but which were not sufficiently investigated during life to settle the diagnosis.

The conclusion to be drawn from these reports is that plague has existed—

(1)    In Eppstein and McCann, when admitted from Gawler.

(2)    In Neale, in Knox-street, city.

(3)    Among rats, both at the Adelaide Hospital and in the city.”

The detailed evidence regarding these three, and other reported cases, is set out in a comprehensive manner by Dr. Ramsay Smith in the report above quoted.

Dr. Borthwick, Medical Officer of Health for the City of Adelaide, has recorded his douhts (Aust. Med. Gaz., 20th Oct., 1900, p. 433) whether any of the cases officially accepted as plague in South Australia in 1900, were in fact true plague. To this general position he makes an exception of the case which occurred in the Gera, a vessel which came from Sydney. With reference to these cases the divergence of opinion was not limited to South Australia. Apparently the Victorian Health Department did not entirely accept the cases as plague. The report of the Board of Public Health for the years 1898 to 1904 inclusive, contains (p. 13) the following statement *—“Plague made its appearance in Australia in March, 1900. On 7th March, 1900, plague appeared at Sydney.” This may he taken as equivalent to a declaration that the Victorian authorities did not recognize the Adelaide cases (which occurred in January) as true plague—although the statement that plague appeared in March is difficult to understand, as the first case in Sydney occurred in January, 1900.

Ashburton Thompson [Plague at Sydney, 1900, p. 22], says of these cases:—“It was announced on 15th January, 1900, that certain cases had occurred at Adelaide, South Australia, which were considered to he plague. The detailed accounts, when they came to hand, hardly pourtrayed plague under its clinical or its epidemiological aspects. The rumour, which from the first had been regarded with doubt, was ultimately discredited.”

Whatever views may he held as to the merits of either side in this controversy, it is impossible, in an historical account of the present kind, to do more or less than accept the cases officially accepted and recorded as plague by the Department of Health of South Aus tralia. These cases are indicated above as accurately as information now available will permit.

The epidemiology of these cases is obscure. The first case. Eppstein, was a seaman, who had arrived in the State of South Australia on a sailing ship, Formosa, direct from JNew York. He had been six weeks in South Australia when he took ill. The other tAvo cases were residents of South Australia, and the records do not contain any reference to epizootic plague antecedent to these cases.

1909.

On 6th April, 1909, tAvo cases of plague (G.F.C. and A.C.) Avere notified to the Local Board of Health at Port Adelaide. In each of these cases the diagnosis Avas confirmed by laboratory tests.

Subsequently, three other cases occurred, the last being on 5th June.

All tlie patients were men wlio worked in connexion witli shipping, either on ships or on the wharfs.

Prior to the occurrence of the first case, there had been no dead rats found with any suspicion of plague, and it was assumed that the infection in these cases was obtained from shipping, but, at a later stage, the occurrence of rat plague on the wharfs at Port Adelaide was established, and it is probable that all the cases had been locally infected at Port Adelaide.

The last infected rat was found on 19th June, 1909.

On 12th July, 1909, the Central Board of Health took over the sanitary administration of Port Adelaide, and after that date there was no further case.

The following is a statement of the actual cases :—

Date of Notification.

Date of Death.

Recovered and Discharged.

G.F.C. .

6.4.09

6.4.09

A.C. .. .

6.4.09

14.5.09

G.S. .

23.4.09

23.4.09

W. T. .. .

After death

19.5.09

C.G. ..

99 99

5.6.09

C.5769.-2

The following details regarding plague in Victoria are taken from the “ General Report for the Years 1808 to 1904 by the Board of Public Health, Victoria ”:—

1900.—“On 7th March, 1900, plague appeared at Sydney, and on 27th March, plague-infected rats were discovered in Melbourne. At the end of April a case of plague, discovered by the Port Health Officer on the s.s. South Australian on her arrival at Melbourne from Sydney, was isolated at the Nepean Quarantine Station. The first Victorian case of plague occurred on the 8th May, and between that date and the 13th June, nine additional cases (five being in one family) were discovered, two of which proved fatal. Of the above cases one was discovered at Geelong and one on H.M.S. Cerberus, in Hobson’s Bay; the remainder occurred in various parts of the metropolis, viz., Collingwood, Port Melbourne, Camberwell (each one case), and Kensington (five cases).

No case of plague occurred in Victoria during the year 1901, though the disease reappeared in other Australian States.

1902.—In March, 1902, a case was discovered in Fitzroy, Melbourne. This is, so far (30th March, 1906), the last case that has occurred in this State.

The total number of cases that have occurred in Victoria since the appearance of the disease in Australia is eleven, with two deaths, ten of these cases having taken place in 1900, and one in 1902.”

1907.

On the 17th May, 1907, a case of plague was reported by the Medical Superintendent of the Melbourne Hospital. On inquiry it was ascertained that the patient was a steward from the s.s. Arawatta, which had arrived on the previous day. The patient was isolated, and died on 21st May. No other case was reported.”

[Report of the Board of Public Health for the years 1905-6-7, p. 9.]

There is no record of any further case of plague in Victoria.

The following is a tabulated list of the cases:—

Table 20.

Case.

Date of Report.

Residence.

Remark«!.

1

8th May, 1900

Collingwood

Frequented wharfs

2

10th May, 1900

Port Melbourne

Frequented wharfs

3

11th May, 1900

H.M.S. Cerberus

Probably acquired ashore

4

14th May, 1900

Geelong

In Geelong four days only; came from South Melbourne

5-9

21st May, 1900

Kensington

All in one family

10

5th June, 1900

Camberwell

Market gardener ; dead rats on premises ; carted manure from Melbourne

11

4th March, 1902

Fitzroy .

Lumper on wharf; “ apparently infected on s.s. Coolgardie

12

17th May, 1907

s.s. Arawatta .,

Steward

Introduction of the Disease.

Tlie first indication of tlie presence of tlie disease in Western Australia was the deatli of a patient in the Fremantle Hospital on Stli April, 1900. Tlie first case was not suspected to be one of plague until the time of his death, when the nature of his illness being a little obscure it was thought well to make a post mortem examination. The result of this was to establish with definiteness the presence of plague in this case. It is not likely that there had been other cases before this one, for the number of medical men in Fremantle is small, and all reconsidered their recent cases in the light of this death without being able to recall any other in the least suspicious.

This first case was a man, aged 19, who was by occupation a shunter in the railway yards attached to the wharf. It is stated in the official records that “ he had recently been engaged in handling cargo from Sydney.” Apparently the deduction intended by this is that lie was infected by this cargo. The real truth as to the actual origin must remain always undetermined. From a detailed consideration of the location of the cases in the first epidemic it was seen that the man lived as near to the wharfs as it was possible for him to do, so that the possibility of infection direct from a ship or as the outcome of a rat epizootic ashore or both exists.

Association with other Epidemic Centres of Plague.

Vessels called at Fremantle regularly from other Australian ports, including Brisbane, Sydney and Adelaide, between which ports and Fremantle there was a regular weekly service. Vessels also arrived regularly from Singapore, Colombo, Calcutta, Bombay and South Africa. It becomes, then, necessary to examine the possibility of spread of infection from these ports to Fremantle with the consequent establishment of a rat epizootic in the latter port.

Sydney.—The following facts are taken from the report of the first outbreak of plague in Sydney by Ashburton Thompson:

“ Beyond pointing out the several ports from which plague might have been introduced into Sydney, and the great number of vessels which arrive from those ports during each year, nothing can be said as to the way in which the disease was actually introduced.” On 14tli February, 1900, the existence of an extensive epizootic of plague amongst the rats was definitely determined. “No information concerning mortality among rats was furnished in response to .    .    . inquiries until 14th February.’ “At a later date it

transpired that an unusual mortality among rats had been noticed as far back as the first week in January.” The first human case of the disease occurred on 20tli January, 1900.

Although, as Dr. Thompson states, precautions were taken with outgoing shipping after the existence of the epizootic was known, yet there must have been a longer or shorter interval before these precautions were instituted during which infected rats may have made their way on board vessels bound for Western Australia. This possibility

is rendered greater by tlie fact tliat tbe epizootic in Sydney was found to liave existed earliest at tliose wliarfs at wliich Western Australian vessels were loaded.

Tliat the measures taken by tbe Sydney authorities after the existence of the epizootic became known to them were in certain respects efficacious is evidenced by the fact that a report by the Chief Inspector of the Western Australian Central Board of Health, dated 20th May, 1900, refers to the strong sulphurous odour pervading all the cargo of a certain vessel and the discovery of rats killed by the sulphur.

In the absence, then, of any more definite evidence, all that can be said of Sydney as a possible source of infection is that at the time of the occurrence of the first case in Fremantle (8tli April) the epidemic was well established in Sydney, that the epizootic was also well established, but that measures were being taken on all outgoing vessels for some time before the appearance of plague in Fremantle. (The proclamation dealing with the fumigation of vessels was issued on 30th March, 1900). If, therefore, Sydney was the source from which Fremantle was infected, there was probably a transmission of infection from Sydney to Fremantle some appreciable time before the first human case at Fremantle (8tli April).

Adelaide. A case of plague was reported from Adelaide on 15th January, 1900. About this case, however, there was considerable controversy, and Dr. Ashburton Thompson, in his report above quoted (p. 32) throws doubt upon the diagnosis of plague in this case. There has not been any evidence that the port of Adelaide was at this period the scene of any epizootic amongst rats and it is probable that the infection at Fremantle was not brought from Adelaide.

Brisbane.—On 5tli March, 1900, a rat was found on one of the Brisbane wharfs dead, and the cause of death was established as plague. Subsequently a human case occurred on 27tli April—this was the first case amongst the residents of Brisbane. Other cases had, however, occurred. On the 17tli April, at Rockhampton, a steward on the s.s. Bur w ah' fell ill with plague. (See pages 25 and 71.)

These and other facts are considered by Dr. Ham (from whose reports all the facts are taken) to justify his conclusion that the disease was introduced into Brisbane and Rockhampton by plague infected rats from Sydney.

Speaking of Brisbane, he says that “ an unusual fatality amongst rats had taken place prior to the occurrence of the first case in man on 27th April.”

In Brisbane, therefore, as in Sydney, there was an unrecognized epizootic for some longer or shorter time before measures were taken against outward going vessels. As, however, the first case occurred in Fremantle 22 days before the case in Brisbane—and the length of time during which rats were infected in Brisbane before the fact of their

infection was determined is not known—it may reasonably be said that tlie probability of the Fremantle infection coming from Sydney is greater than the probability of its coming from Brisbane.

Melbourne.—A few cases of plague occurred in Melbourne, but the first case there was on 8th May, while the first case in Fremantle was attacked on 5tli April, 1900.

Course of the Epidemic.

The following is a tabulated statement of the cases which occurred during 1900, and during the subsequent outbreaks:—

Table 21.

1900.

No.

Place.

‘Initials.

Age.

Attack.

Result.

1

Fremantle . .

w.c.

19

5th April . .

Died, 8th April

2

99 * ’

s.w.

24

8th April . .

Died, 12th April

3

99 * *

A.M.

43

13th May . .

Died, 15th May

4

J.F.

40

6th June ..

Recovered

5

K.M.

23

12th June . .

Recovered

0

99

H.S.

14

17th June ..

Recovered

1901.

No.

Place.

Initials.

Age.

j\ tta c.k.

Result.

1

Perth . .

J.K.

1st March . .

Died, 4th March

2

99

A.F.

40

28th/February

Died, 8th March

3

9 9

H.G.

30

28th February

Recovered

4

J.C.

12th March . .

Recovered

5

C.F.

19

11th March ..

Recovered

6

C.L.

42

13th March . .

Recovered

7

D.W.

19

15th March . .

Recovered

8

F.S.

19

16th March ..

Recovered

9

W.D.

5

17th March . .

Recovered

10

E.B.

33

18th March . .

Recovered

11

F.S.

36

17th March . .

Recovered

12

E.B.

23

19th March . .

Died, 1st April

13

Fremantle ..

S.J.

22nd March . .

Recovered

14

Perth . .

P.S.

24th March . .

Recovered

15

D.S.

19

14th April . .

Recovered

16

Kalgoorlie ..

J.T.

50

26th March . .

Recovered

17

Perth . .

G.L.

4

16th April ..

Recovered

18

H.C.

48

17th April ..

Recovered

19

H.B.

23

19th April . .

Recovered

20

9 9 * *

A.K.

40

14th April . .

Died, 27th April

21

Fremantle . .

A.C.

21

28th April . .

Recovered

22

Perth ..

G.M.

28th April ..

Died, 1st May

23

99 * *

W.F.

32

11th May ..

Recovered

It is oificially recorded that the Kalgoorlie case was infected in Perth.

1902.

No.

Place.

Initials.

Age.

Attack.

Result.

1

Fremantle . .

E.P.

24

19th May ..

Died, 25th May

2

99

J.M.

17

15th May .

Died, 22nd May

3

99 • ‘

C.L.

32

4th July .

Died, 8th July

No.

Place.

Initials.

Age.

Attack.

Result.

1

Fremantle .

H.M.

19

24th January..

Recovered

2

99 • *

N.B.

20

27th January..

Died, 29th January

3

99

L.B.

23

27th January..

Recovered

4

99 * *

R.S.

15

10th February

Recovered

5

99 • •

P.C.

27

15th February

Died, 18th February

6

99 * *

N.R.

15

17th February

Died, 24th February

7

99 9 9

J.G.

52

19th February

Recovered

8

99 • *

V.H.

26

24th February

Died, 28th February

9

99 • •

E.C.

52

22nd May . .

Recovered

10

South Perth ..

A.D.

32

26th September

Died

11

99 • •

A.T.

26th September

Died

12

99 m *

A.S.

32

26th September

Died

13

Bellevue ..

J.G.

6th November

Died

1904.

No.

Place.

Initials.

Age.

Attack.

Result.

1

Perth .

J.L.

43

21st June .

Recovered

2

99 • •

P.D.

14

29th June . .

Died, 4th July

3

Fremantle . .

J.M.

54

28th July . .

Recovered

4

99

W.P.

27

19th August ..

Recovered

1905.

Ml.

1906.

No.

Place.

Initials.

Acre.

Attack.

Result.

1

Perth ..

N.P.

9th January ..

Recovered

2

99 *

G.L.

14

28th January..

Recovered

3

99 • •

W.D.

16

7th February..

Recovered

4

Fremantle ..

G.F.

44

10th February

Died

5

99 • •

A.F.

33

10th February

Recovered

6

99 • •

F.F.

6

11th February

Recovered

7

99 • •

D.G.

3

13th February

Died

8

99 • •

P.J.

40

19th February

Recovered

9

Geraldton ..

M.K.

19th February

Died, 22nd February

10

99

L.G.

19th February

Died, 24th February

11

99 • •

C.G.

19th February

Died, 22nd February

12

99 • •

W.A.

21st February

Died, 24th February

13

99

J.B.

21st January ..

Died, 24th January

14

Fremantle ..

E.B.

22

17th February

Recovered

15

Geraldton ..

W.B.

23rd February

Died, 5th March

16

9 9 * '

H. D.

18th February

Died, 27th February

17

Perth ..

J.R.

24th February

Recovered

18

99 *

H.H.

28th February

Recovered

19

Geraldton ..

E.C.

2nd March ..

Recovered

20

H.M.

8th March ..

Recovered

21

Fremantle ..

P.R.

26

19th March ..

Died, 21st March

22

99 * •

C.K.

21st March ..

Died, 27th March

23

C.D.

15

21st March ..

Recovered

24

M.W.

57

20th March ..

Recovered

25

M.L.

26

24th March ..

Recovered

26

P.B.

23

25th March ..

Recovered

27

Geraldton ..

E.C.

. .

15th February

Died, 18th February

28

Fremantle ..

E.F.

26

28th March ..

Recovered

29

Perth ..

A.T.

24

10th May ..

Died, 15th May

30

Fremantle ..

R.B.

39

29th May ..

Died, 2nd June

31

99

H.F.

20

23rd May ..

Recovered

39

Table 22.

Monthly Distribution of Hitman Plague in "Western Australia.

Reported Plague at Geraldton (W-A-), 1909.

One case of plague was reported in 1909 at Geraldton, and after the death of the patient, the medical attendant certified that the death was due to plague. The patient came from far inland, and bacteriological examination with careful inquiries established that the case could hardly be legitimately regarded as one of plague.

The official report to the Health Department by the medical man who certified to plague as the cause of death contained the statement that the immediate cause of death was abscess of the liver.

CHAPTER VII—IMMUNITY OF TASMANIA.

The State of Tasmania was not invaded by plague at any time during the course of the epidemics on the mainland.

SYDNEY

OTHER PARTS OF NEW SOUTH WALES

Human

Rodent


BRISBANE


OTHER PARTS OF QUEENSLAND


VICTORIA


Human

Rodent


Human

Rodent


Hum an Rodent


imi

udtdi


Human

Rodent


SOUTH AUSTRALIA

WESTERN AUSTRALIA


Human

Rodent


1—rrr

Fig. 2. Diagram illustrating the reported Course of Infection in Different Localities in Australia, 1900-1910.

(Hatched areas represent human infection; blocked areas represent rodent infection ; triangular areas indicate that scattered

infection only occurred during the year.)

CHAPTER VIII—THE COURSE OF PLAGUE IN AUSTRALIA, 1900-1909.

The course of plague in its epidemic, as contrasted with its •epizootic, manifestations, throughout Australia, may now be reviewed. The disease, appearing first in 1900, continued until 1909—a period of ten years. The following table shows the numbers of cases in each of the States for each of the years concerned:—

Table 23.

1900.

1901.

1902.

190:L

1904

1905.

1900.

1907.

190S.

1909.

Total.

New South Wales . .

303

2

138

2

12

57

20

51

6

23

614

Victoria . . . .

10

1

. .

1

12

Queensland . .

136

36

91

29

35

56

32

53

29

2

499

South Australia . .

3

4

7

Western Australia . .

6

23

3

13

4

31

80

Tasmania . .

nil

nil

nil

nil

nil

nil

nil

nil

nil

nil

Total . .

458

61

233

44

51

113

83

105

35

29

1,212

The total number of cases, therefore, in Australia for the whole period of ten years was 1,212. In order that these may be summarized according to locality distribution, the following table is compiled:—

Table 24.

Lorality.

1900.

1901.

1902.

190:?.

1904.

1905.

1906.

1907.

190«.

1909.

Total.

New South Wales. Metropolitan . . . .

303

2

137

2

12

18

20

47

6

23

570

Newcastle . . . .

1

14

15

Ulmarra . . .

13

13

Ballina . . . .

4

4

Lismore . . .

8

8

Kempsey .. ..

4

4

Victoria.

Metropolitan

10

• •

1

1

12

Queensland.

Metropolitan . .

56

36

82

21

30

28

11

40

14

318

Ipswich .. . .

1

1

8

2

12

Rockhampton . .

36

2

11

49

Townsville . . . .

37

7

3

6

1

54

Charters Towers . .

1

1

Cairns . . . .

5

1

2

2

10

14

34

Bundaberg . . . .

i

2

1

4

Gladstone . .

i

1

Maryborough . .

2

10

12

Childers . . . .

1

1

Port Douglas . .

10

10

Mackay . . ..

1

2

3

South Australia.

Metropolitan . . . .

3

• •

4

7

Western Australia. Perth . . . .

20

4

2

6

32

Fremantle . . . .

6

2

3

9

2

15

37

Geraldton . .

10

10

Kalgoorlie

1

1

Annual Totals

458

! 61

233

44

51

113

83

105

35

29

1,212

From considerations of plague epidemiology, the course of plague in Australia is of very great interest.    There are some prominent

features which at once arrest attention.    These features are readily

appreciated by a reference to the accompanying maps of the Commonwealth, on which are indicated the places at which plague occurred. The first point which attracts attention is that Tasmania entirely escaped infection, while Victoria and South Australia were only very lightly invaded. The case shown in Victoria as having occurred in 1907 was not actually a Victorian case, as it occurred on a vessel on its way to Victoria from Queensland ports, so that a total of eleven cases only occurred in a metropolitan population of 500,000. In South Australia, also, in a metropolitan population of 200,000, only seven cases are recorded.

Fig. 3. Map of Australia, showing localities where Plague occurred, 1900-1909.

In Western Australia, Perth and Fremantle may be considered as one district. Fremantle is the seaport of Perth, the capital city, being distant only 13 miles, and there is constant water-carriage by lighters between the two cities of merchandise brought overseas or from the other States. The case at Kalgoorlie will be considered in detail at a later stage; but, for present purposes, it may be ignored as having no general epidemiological significance. The only other centre attacked was Geraldton, a seaport town, some 215 miles north of Perth.

In New South Wales, the epidemic commenced vigorously, subsided «luring 1903 and 1901, becoming again slightly active in 1905, 190G, .    1 1907; subsiding again to vanishing point during 1908 and 1909.

Even in the years 1905-1907, the disease did not manifest any degree

1900


f Hf M<VNTl

1905


C ^iQNb

TO WN SV 1 LLE

ounoaberg

. • ^Y^A^BOROOGH #) BRli>0AN€

S^r-\

J IHORT MEON

/ RiVtRS NF%NCAiTtE


1901


fREWANT^f,

6Rl bB^VN £

•/5Y ONE Y


1906


C^lQN-

CERALOTOM'

F«t Wftu TlE

OCftHAMPTO M

#1 0 « IS IUnI

SYDNt Y


1902


FREfAANTLI

Town>v l LL£

aostone Bu^OABf Rii BC\i i*0 AN E

BOUUNE


1907


POR.T OOvJCC AS C f\ i Q. N 5

TOWISSVULE

iPbWiCH # flk 8R*M3AN E

tf •


1903


Faer^ANTLe

vhim e y


CM R.NS

is. Townsville

^OCMAMPTOM

♦»6UNDABERC

»

M Brisqan e


1908


BRISBANE

SYDNEY

9


1904


N4«YBO«OUCM

• '


*PSW.CM*'iBRlSOikNE

/ NfORTHC PUN

J Rivers-

SYOnEY


1909


SY ON e Y


Fig. 4. Localities in which Plague occurred in each year, 1900-1909.


of activity comparable with that of the years 1900-1902. During the whole ten years during which epidemic plague persisted in Sydney, there were only three separate years in which cases occurred outside of the metropolitan area. In 1901, one case occurred at Newcastle, and in 1907, four cases occurred at Kempsey. These two. years were clearly not characterized by any material extension of the disease outside the metropolitan area. In the year 1905, however, there were 14 cases at Newcastle, and a total of 25 cases at IJlmarra, Ballina, and Lismore—a group of country towns which will be shown later to he closely related in epidemiological association. It is an important feature of the occurrence of plague in Australia that Newcastle, an important city seaport, with a population of 45,000, situated only 70 miles by sea from Sydney, with an immense volume of inward and outward shipping, and in constant communication with Sydney, both by rail and sea, should have escaped infection during eight years out of the ten—excepting the one isolated case of 1902—and when infected should have had a total of only fourteen cases.

In Queensland, the principal features were the uniformity of the annual incidence during the nine years 1900-1908; the fact that the three principal seaports (Rockhampton, Townsville, and Cairns), were infected in the first year (1900), and remained infected until 1906, 1907, and 1908 respectively; the progressive infection of all Queensland ports of any importance; and the fact that, except for a total of twelve cases at Ipswich—-which is in constant communication with Brisbane by water-route—no case occurred in any locality other than a seaport. The single cases at Charters Towers and Childers may be ignored for the purposes of this general statement.

The type of infection amongst humans remained bubonic throughout the course of the outbreaks. On two occasions only was there reported a localized spread of pneumonic infection. In Sydney in June, 1906, fatal pneumonic plague was determined in the wife of, and in a neighbour who attended, a fulminating case of pneumonia in a seaman (P.R., 1906, p. 7). Amongst 29 other close contacts, including 9 children in the family of the primary case, there were no further cases. The family lived in comfortable circumstances in a 7-roomed house in Balmain. At Maryborough, Queensland, in May-June, 1905, seven children of a family in very poor circumstances developed what was apparently septicaemic plague, and five of them died with secondary pneumonia. A neighbour in attendance and two hospital nurses contracted pneumonic plague and died. (Ham, Special Report,

1903.)

CHAPTER IX—EPIZOOTIC PLAGUE IN AUSTRALIA.

At tlie time wlien plague first made its appearance in Australia, the importance of the part played by rats in the epidemiology of the disease was not officially, or even generally, recognized. For this reason, the information concerning plague in rats is not complete for the earlier years of the epidemic, although, thanks to the intelligent recognition by such distinguished hygienists as Gresswell and Thompson, the importance of measures directed against rats was recognized from the outset. There is clear evidence of this, not only in the contemporary reports, but in the provisions of the Australian Plague Convention of 1900 (see Appendix A). This latter Convention, to which subscribed five of the six Australian States—New South Wales not participating in the Conference—was adopted at a Conference which sat on lltli, 12tli, and 13tli April, 1900. The Convention was based on the Venice Convention of 1897; but, although this latter Convention contained no reference whatever to the role played by rats in plague, the Australian Plague Convention of 1900 contained definite provisions dealing with this aspect, as follows:—

“ All vessels to he disinfected at once after discharge of cargo to the satisfaction of the health authority, and all practicable measures to he taken for the destruction of rats.

When a reasonable suspicion of danger from plague arises, the destruction of rats by poison at sea and land frontiers to be immediately undertaken and vigorously prosecuted, the expense of this procedure, as far as regards shores, river banks, piers, and wharfs, to be borne in the first instance by the Government; and the several Departments of the State, and the local sanitary authorities, to immediately undertake and be responsible for the extermination of rats on their several properties, or within their several districts; and the bodies of all rats taken alive or dead to be destroyed in every case by fire.”

The records of the progress of epizootic plague, incomplete at first, become more detailed and exact as the experience gained with each successive outbreak indicated the nature of the information to be obtained, and of the records to be kept.

APTER X.-THE EPIZOOTIC IN NEW SOUTH WALES.

Epizootic Plague at Sydney.

1900.—From May, 1894, to December, 1899, tbe treatment accorded to vessels arriving from ports infected with plague was that prescribed by the Venice Convention of 1897. But when it was announced that plague was epidemic at Noumea, attempts were made to kill any rats which might still remain on vessels from plague-infected ports, notwithstanding the efforts to the same end which had usually been made at the port of departure.

On 25th January, 1900, the first case of human plague at Sydney was made known. The circumstances attending the occurrence of this first case caused the Board of Health to insert advertisements requesting information from owners or occupiers of wharfs, stores, and warehouses, masters of vessels, scavengers, and the public in general, as to unusual mortality or unusual movement among the rats at places under their control, and attempts were made in other ways to obtain such information. No information concerning mortality among rats was furnished in response to these advertisements, nor to other inquiries, until lltli February, when an officer in the Customs Department drew attention to unusually frequent deaths amongst rats at Huddart, Parker and Company’s wharf. During that day, four live rats and three carcasses were brought to the Board of Health laboratories. These seven rats were proved to be infected with plague. At a later date, an official reported that he had noticed an unusual mortality among the rats at Huddart, Parker and Company’s wharf about the first week in January; but no confirmation of this was ever forthcoming. The disease was not introduced into New South Wales either by some unobserved imported case in man, or by importation of infected articles, but by infected rats; from which it spread to the local rats, which in turn communicated it first to case 1, and afterwards to other persons. But by what vessel, or from which infected port, such rats were landed at Sydney, there is no evidence. During the course of the epidemic of 1900, 167 rats were examined, and plague bacilli were detected in 28 of these. Actually, however, many reports of dead rats were received, and it would be erroneous to suppose that the 23 proven infections were the only occasions of the presence of rodent plague rats over a considerable area of Sydney, which was the area on which cases of plague in man occurred, suffered from epizootic plague. This epizootic began before plague in man occurred, and ceased, as far as can be learnt, about the same time as the epidemic ceased.

Thompson, from whose “ Report of the Outbreak of Plague at Sydney, 1900,” the above remarks are quoted practically verbatim, summarizes as follows

An epizootic disease among rats preceded the first case which occurred in man.

This epizootic disease was plague.

The area over which the epizootic extended was practically co-extensive with that on which cases of plague in man were observed.

The epizootic died out, as far as can be learned, at the same time as the epidemic ceased.

The epidemic was caused by communication of the infection from rats to man.

The last infected rat was located on 12th July, 1900.— (Map B, Plague Reports, 1900.)

1901 and 1902.—The monthly distribution of epidemic and epizootic plague during the years 1900, 1901, 1902, is shown in the following table :—

Table 25.

Year.

Month.

1

Number of Per-

Number of

sons Infected.

Plague-rats Identified.

1900 ..

January

1

February

3

9

March

51

2

April

107

6

May

93

5

June

41

1*

July

6

August

September

October

November

1

December

1901 ..

January

February

March

April

May

June

July

August

September

October

November

1

4

December

1

1902 ..

January

6

5

February

26

25

March

57

6

April

20

37

May

22

23

June

6

4

July

August

September

October

November

December

1

* The fact that the last plague-infected rat is here recorded as having been identified in June iajtead of July, as above recorded, is as recorded in the original reports (see Piague Reports 1902, p. 60.)

As to the origin of this second epizootic and epidemic, Thompson remarks as follows:

“ The only hypotheses worth serious examination, in our opinion, are the two following: Either the epidemic depended on a recrudescence of the epizootic of 1900, or upon a second epizootic set going by newly imported plague rats. As to the former, we had reason to believe that the epizootic of 1900 died out in the course of that year; but the evidence gathered was insufficient to establish the fact; still, the recurrence was apparently too long delayed to have been a recrudescence, the interval of fifteen months which elapsed before the disease again occurred having extended far beyond the time at which generations of new and susceptible rats had come into existence. Further, it will presently be shown that the state of rats as to disease was very carefully, and it is thought completely, ascertained over the whole of the threatened area from conclusion of the epidemic in June, 1902, to 31st December; while from the latter date the wharfs were watched in the same thorough way until far into 1903. Now, the last plague rat was discovered on 13th July, 1902; consequently, there is good ground for asserting that the second epizootic, at all events, died completely out; and, therefore, as regards commencement of the second epizootic, the balance of evidence at Sydney appears to tell in favour of reimportation.”— (P.R., 1902, p. 11.)

1903.—Attack occurred in the last human case of the preceding outbreak on 12th June, 1902; the last plague-rat was taken on 14th July,

1902.2 The 1903 outbreak began in an epizootic of plague, of which the first evidence was got on 12th May, 1902, and the last on 15th August, 1903.

Thompson in his reports deals, for the sake of convenience, with three periods—(a) from 15th July, 1902, to 30th April, 1903, being the preliminary plague-free period; (b) from 1st May, 1903, to 15th August, 1903, being the epizootic period; and (c) from 16th August to 31st December, 1903, comprising a large part of the ensuing plaguefree period. During the first of these periods, the rat-catching staffs continued at work, and during the whole of the first of the three periods, 31,075 rodents were taken, of which 17,160 were examined in the laboratory; and these rodents had been taken in neighbourhoods selected in accordance with the experience which had taught that recurrent plague would probably first betray itself in them. None of the 17,160 were infected with plague. Thompson claims that Sydney had actually been rat-free during the period in question. He says:—“ On the whole, it appeared, on 30th April, 1903, to be probable that Sydney had for eight months and a half been really free from plague in its rats, as it certainly had been free from plague in man.-—(P.R., 1903, p. 2.)

On 8tli May, 1903, plague-infected rats were found in a produce store. From that date until 15tli August, 8,695 rats and 5,976 mice were examined at the laboratory. Of these, 111 rats and 50 mice were found to he plague-infected. From 15th August until 31st December, 1903, a total of 13,389 rodents was examined without the discovery of one plague-infected individual. Thompson claims that, ” at the end of 1903, it once more appeared that Sydney had been free from epizootic plague for four months and a half.”

1904—The first direct evidence of epizootic plague in this year was got on 1st March, 1904, the last on 3rd December. Following his previous practice, Thompson establishes three periods:—the precedent plague-free period from 16th August, 1903, to 29tli February, 1904; the epizootic period, from 1st March to 3rd December; and the ensuing plague-free period from 4tli to 31st December, 1904.

The number of rodents destroyed during the precedent plague-free period was 78,161, of which 18,456 were examined—all being free from plague. During the epizootic period, the total number of rodents destroyed was 108,936, of which 43,822 were examined. Among them, 181 rats and 62 mice were found to be infected with plague.

From 4th December to 31st December, 8,231 rodents were destroyed, of which 3,145 were examined without the discovery of any plague infection.

Thompson, at this stage in the evolution of plague in Sydney, was able to say, with regard to the 1904 cases, “ Close association with plague-rats was shown to have existed in every one of the series of cases which constituted the outbreak under review.” And he was able to state that his deductions in 1900 (see p. 47) remained substantially unaltered. These deductions included, inter alia, that important conclusion that “ the area over which the epizootic extended was practically co-extensive with that on which cases of plague in man were observed.

1905. It was remarked previously that the importance of accurate and detailed records of rats in relation to plague was not generally recognized in f900. By 1904, the relation had become very generally accepted, but difficulties were experienced in the making of detailed observations. Thompson’s report for 1905 states the position:

“ During the outbreak of 1904, a special effort was made to

'ascertain whether close connexion between cases and plague-rats could not be established in every instance, provided sufficient time were devoted to the search; and it was made with reference to two points. One was the difficulty, thought to be merely incidental, which had so often prevented demonstration of the presence of plague-rats on premises which had proved themselves to be infective, and the consequent incompleteness of the evidence, which in

general supported the view that rat-plague is a condition precedent of plague in man. The other was the desirability of examining more exactly into cases where it was thought, after due search, that neither rats nor signs of infestation by rats were present, which had appeared to have been the case in a very few instances; in which, nevertheless, presence of plague-rats in the immediate neighbourhood had been ascertained. However, while only twelve cases occurred in connexion with nine places of infection, the presence of plague-rats at each place was established; so that no opportunity of further examining the second point then offered.

As far as it went, that evidence was against the soundness of the observation which had been made, namely, that very rarely a house might prove to be a place of infection in absence of signs of infestation by rats; still, the point has been noted for further inquiry. But, although in the year referred to the number of cases and of places was extremely small, it had been found that the labour involved in the constant watchfulness of all concerned, which turned out to be necessary to success, and of long quasidetective inquiries, were too great to be continued by a staff whose daily avocations were multifarious and exacting. During the year now reported upon, therefore, no special attempt was made to run the plague-rat down in connexion with every case, although the more salient points were as carefully recorded as usual.”—P.R., 1905, p. 1.)

The three periods to be considered in this year were:—(a) the precedent plague-free term from 4th December, 1904, to 17th January, 1905; (b) the epizootic period, from 18th January to 5th December; and (c) the subsequent plague-free period, from 6th December to the end of the year. This latter period, it may be noted here, lasted only 49 days, the first plague-rat of 1906 having been taken at the Baltic Wharf, Darling Harbour, on 23rd January, 1906.

During the precedent plague-free period, 4th December to 17th January, 5,086 rodents were examined and found to be plague-free. During the epizootic period, 18th January to 5th December, 28,446 rodents were examined, among which plague was identified in 123 rats and 18 mice, a total of 141 rodents.

Prom 6th December to the end of the year, 956 rodents were examined and found to be plague-free.

With regard to the commencement of this 1905 epizootic, Thompson finds the explanation as follows:—“ Recommencement of the epizootic at Sydney—19th January, 1905, at the Horth Coast Steamship Company’s Wharf—was thought to have resulted from re-introduction of

the infection from a district on the northern coast-line of the State, which itself was probably infected by sea from another source than Sydney ”—(P.R., 1904, p. 2.)

1906. —The last plague-rat in 1905 was identified on 5th December. In 1906, the first plague-rat was identified on 23rd January, and the last plague-rat was identified on 29th December, 1906. During the precedent plague-free period, 6th December, 1905, to 22nd January, 1906, 3,225 rodents were examined without the discovery of any evidence of plague, During the epizootic period, 23rd January to 29th December, 27,731 rodents were examined, and plague was identified in 135 rats and 39 micei—total, 174.

1907. —In 1906, the last plague-rat was taken on 29th December. In 1907, the first rat in which plague was identified was taken on 10th January, the last on 21st September. Attack in the last human case occurred on 29th December, 1907; but plague-rats in number were discovered in connexion with it; and with another which preceded it (attacked 27th December) as soon as search had proceeded sufficiently, namely, on 2nd January, 1908. During the whole year, 31,621 rodents were examined, of which 219 were plague-infected.

1908-1920^—For the years subsequent to 1907, the following table may be given :—

Table 26.

Year.

Total Rodents Examined.

Total Infected.

1908 .. .

26,849

175

1909 .. .

26,737

178

1910 .. .

22,821

5

1911 .. .

22,774

1912 .. .

17,154

1913 .. .

10,615

1914 .. .

9,439

1915 .. ..

9,673

1916 .. .

7,943

1917 .. .

8.231

1918 .. .

7,779

1919 .. .

3,165

1920 .. ..

6,667

Monthly Distribution (1900-1912) of Plague Eats identified in

Sydney.

Tlie examination of rodents was continued systematically after tliis period, but no infected rodent was discovered in New Soutli Wales until

1921.

Epizootic Plague in Extra-Metropolitan Districts, New South Wales.

1902. Neivcastle—In connexion witli the single indigenous case of human plague, which occurred at Newcastle in 1902, there was some evidence of antecedent rodent plague. The patient became suddenly ill on 3rd August, and was reported to the Medical Officer of Health on 6tli August. After the preliminary inspection of the premises on 6tli August, the Medical Officer of Health had reported the finding of a dead rat, too decomposed for laboratory examination, and that the licensee had stated that shortly before the patient’s illness he had found other dead rats. On complete inspection of the premises, abundant evidences of rat-infestation were found, and it was recorded that the patient had removed eight dead rats from the cellar shortly before he became ill. During cleansing, four other carcasses, but no live rats, were found. The basement of this building communicated directly, by means of an unused drain, with a wharf. At this wharf, very large quantities of fodder had been landed during several previous months, either from ships or from the adjacent railway. This fodder was almost or entirely the produce of New South Wales, and had, no doubt, been exposed to incursions of rats during its collection at Sydney.

The rat-destruction operations, which, begun in 1900, had been discontinued in 1901, were recommenced on 6tli March, 1902. Special measures were applied after the discovery of the human case; and

between 8tli August and lltli September, rats were collected from 125 different premises. A total number of 1,598 were collected, in none of which was the presence of plague established.

Thompson comments as follows:—“ It must therefore be recorded that no plague-rats were found at Newcastle. Nevertheless, for reasons which have already been given above, it cannot be affirmed that there were no plague-rats there; and it is a significant fact that no rumour of unusual mortality among the rats of any part of Newcastle was heard during the investigation, except at the Criterion Hotel ” (the premises where the human case occurred).

From Thompson’s account of this outbreak, it is clear that he draws the inference that some infected rats were conveyed from Sydney to the immediate neghbourhood of the Criterion Hotel, at Newcastle; that there was created a local focus at that hotel which did not spread.

1905. Ulmarra.—This outbreak furnishes evidence of primary importance and interest, because being in a limited community it offered exceptional facilities for inquiry, and because Millard, who was alert to take advantage of those facilities, has placed on record an account of exceptional completeness. The first human case occurred on 14th December, 1904. The last human case occurred on 6tli May, 1905. The first rat in which plague was identified was examined on 8tli January. The last infected rat was found on 8tli March. During that period infected rats and mice were found as follows:—

Ulmarra

Examined.

.. 1684 . .

Infected

. . 103

Woodford Island

308 . .

6

Southgate . .

' .. 68 ..

.. nil

Grafton

3.19

. . nil

South Grafton

. . 244

. . nil

“ Of the conditions prevailing among the rats of the Ulmarra district prior to 8th January, nothing can with certainty be said, but from the information locally available, it appeared that rats had been unusually numerous some four to six weeks previously, i.e., about the beginning of December, and that later on dead and sick rats had been seen at several places in the township and along the river bank. The mortality had been commented on, and had been loosely explained by the suggestion that the rats had been poisoned.” On inquiry, however, “ there appeared little reason to suppose that poison had been used at all generally.”

“ The report of previous rat mortality was supported by the finding, on 9th and lOtli January, of 50 rats and 65 mice mummified, in a barn at the residence of case D, and of three rats and one mouse in a similar condition at the residence of cases B, E, and F. Under the existing climatic conditions this mummification would probably be produced in a week or ten days.”

The rumour of rat mortality was not confined to the Ulmarra or right bank of the river. Similar statements were made with respect to the village of Southgate, on the left bank, opposite Ulmarra. No human cases occurred at, or were connected with, Southgate. The epizootic appeared to gradually die down, the last infected rat was obtained on 8tli March, and no further rat mortalit3r was reported from any part of the district. When, some two months later, search for rats was reinstituted in connexion with another case of plague (6th May), it was found that rats were still exceedingly scarce.”

In all of the human cases except the last (6th May) the association between epizootic and epidemic plague was shown to be intimate.

Whence the epizootic infection was introduced, and at what point in the district it first manifested itself can only be conjectured. Ulmarra had commercial relations with both Sydney and Brisbane— with the former by a regular semi-weekly service of steamers, in addition to occasional extra cargo boats, and with the latter by one weekly steamer. There was at that time no overland trade. At Sydney plague-infected rodents had been obtained on 10th October, 1904, at Sussexstreet; on lltli October, at Dalgety’s wharf; on 4tli November and 3rd December, at the A.U.S.N. Company’s wharf. After this last date, though the systematic rat examination was maintained, no more infected rats were brought in until 18tli January, 1905, when one was obtained at the Sydney wharf of the North Coast Steam Navigation Company—the wharf at which the steamers from both the Clarence and the Richmond rivers lie while discharging and loading cargo in Sydney. This was the first of seven infected rats obtained from the same wharf on 18tli, 19tli, 23rd, 24tli and 25tli January.

At Brisbane the official returns report finding of an infected rat on 8tli October, 1904; but after this no more until 21st January, 1905, an interval of 105 days, during which, as far as is officially known, the town and port were free from plague in rats.

From this evidence as to known rat infection at the two places respectively—which, probably, however, cannot be accepted as fully and completely stating the actual conditions prevailing—and from the facts as to relative amounts of trade with Sydney and Brisbane, it would appear that the importation of infection from Sydney was more probable than from Brisbane.

The actual point or points at which the infection was introduced cannot be stated. The most probable theory as to the sequence of events appears to be that the infection was introduced at two points—Ulmarra and Bushgrove; that the epizootic spread was first along the river bank, possibly because the rat population wras more continuously distributed there than elsewhere; that it subsequently at Ulmarra spread through the township, and then from farm to farm in the immediate neighbourhood. The actual vehicle of the infection or infected rats could not bo determined. Among the merchandise imported from Sydney were several kinds which might have served as a means for transporting rats, such as bales of empty bags and empty cases (egg and butter boxes). The imports from Brisbane were, generally speaking, of a less likely character.

1905.—Ballina.—The first positive proof of epizootic plague in Ballina was furnished on 14th February, 1905, when six dead rats were found at Webster’s stables, of which four were demonstrably plague-

infected, and the other two were putrid. The first human case occurred on 3rd February, 1905. Information had been obtained that on the premises occupied by this first human case, dead rats had been noticed about the middle of January. Further examination of Webster’s stables resulted in the discovery of fifteen other dead rats, of which eight were demonstrably infected. Between 11th and 24th February, 403 rats and mice were examined, of which sixteen rats were identified as plague-infected, the last in this series occurring on 17th February. After 17th February there ensued an interval of six weeks until the finding of the next plague-infected rat on 31st March. The plague rats identified occurred as follows:—31st March, 5th and 27th April, 1st, 17th and 19th May— three premises being infected. The epizootic manifestations extended over the period 14th February to 19th May, 1905, during which 28 infected rats and mice were identified. After this period no more plague-infected rats were discovered in Ballina.

Whence the plague rats were introduced to Ballina can only bo conjectured, but it is at least very suggestive that the first case occurred on premises closely related to the wharf used by the Brisbane trader,

the s.s. Pyrmont and that Webster’s stables, which appeared to he the important focus of the epizootic, were connected by an untrapped sewer with the foreshore near the same wharf,

1005.—South Woodburn—On 18th March a dead and a sick rat from Murray’s Hotel, South Woodburn, and on 20th March a third rat from the same hotel, were found to he plague-infected. Between 18th March and 16th April, 249 rats and 80 mice from this village were caught and examined, and one further rat was found to he infected. In addition twelve dead rats were found, hut these were too decomposed for examination.

Ho information was obtainable of any previous mortality amongst rats, hut it was stated locally that about the middle of February the rats had suddenly disappeared from the wharf, which previously had been infested with them. Ho further indications of the epizootic were manifested until 29th May, when a plague-infected rat was found about half-a-mile from the place where infected rats were previously found. The sequence of events at Woodburn, as far as can he conjectured from the meagre data available, was apparently that plague-infected rats were landed at the wharf by steamer, either from Ballina, or by an ocean steamer from Brisbane or Sydney. From the wharf the rats appear to have made their way to the two largest, and to them the most attractive, premises—the hotels. It is possible that the latter manifestation (28th May) was the result of re-introduction of infected rats to Woodburn, as at that date (28th May) there was epizootic plague at both Ballina and Lismore. Ho cases occurred amongst human beings.

1905.—Lismore—Ho unusual mortality among rats appears to have attracted attention at Lismore, until the occurrence, on 1st May, of t.hfirst human case of plague. Then it was learned that a considerable number—nineteen or twenty—of dead rats had been found in a store in the town on 22nd and 25th April. Subsequently the general cleansing operations discovered putrid or mummified rat carcases on several premises in the same neighbourhood, hut it seems improbable that the epizootic had been severe or long established before the occurrence of human cases. When plague first occurred at Ballina in February, Lismore rats to the number of 52 were examined for plague with negative results. On 5th May, a mouse, found dead at some auction rooms, harboured bacilli morphologically resembling B. pest is.

On the first day of systematic examination, namely 12th May, two rats and one mouse were found to he plague-infected. The last plague-infected rats or mice were examined on 13th June. Examination of all rats and mice was kept up for three weeks longer—till 7th July—hut Avitli negative results. In all, a total of 377 rats and 176 mice were examined, eleven rats and eight mice having been identified as being plague-infected.

With tlie exception oi one case, of whose movements no one could give certain information, and who may have been infected at his place of residence, all of the cases notified were connected either with the store above mentioned or with the lane or premises at the rear. It is worthy of note that none of the eleven premises above mentioned as furnishing plague-infected rats furnished patients also, and this although three were hotels and the other premises of such a character as to be much frequented.

Whence the plague-infected rats were introduced into Lismore must necessarily be a matter for conjecture, but the most reasonable supposition is that they were brought up the river. At Ballina plague rats were found in February, April, and May, and at Woodburn in March, April, and May. The frequent communication by steamer between these places and Lismore obviously offered abundant facilities for such transport of rats, despite all precautions, such as rat-guards, tarred mooringlines, &c.

The information relating to epizootic plague at Ulmarra, Ballina, South Woodburn and Lismore, has been taken, almost verbatim, from the excellent reports by Millard. [Plague Beports, ISTew South Wales Board of Health, 1905.]

1905.—Newcastle—The first case of human plague in Newcastle in 1905 was notified on 25tli March, 1905, and the first plague-infected rat was found on 29tli March. On the discovery of this first case of plague in man, steps were taken to provide for the destruction of rats in the city and district. Between 28tli March and 14th August, 1905, 13,901 rodents were destroyed. Of these, 6,653 were examined for plague, and 206 were definitely proved to be infected with the disease. It should be stated that a large number of the rodents brought for examination were too far advanced in decomposition to enable a definite decision to be formed as to the cause of their death, though it was in all probability due to plague, for it not infrequently happened that one or more of a batch found on the same premises were plague-infected, whilst the remainder were too decomposed to allow of a prompt and definite decision being arrived at, though the indications pointed to plague having; been the cause of their death. Leaving this out of account, however, it is still found that 3 per cent. (206 out of 6,653) of the rodents examined were plague-infected. This was a considerably higher proportion than had previously been found in Hew South Wales. The last case .of plague in the epidemic was attacked on 2nd July; the last plague-infected rat was taken on 6tli July; From 6tli July to 14tli August, 594 rats from different parts of the city were examined, but all were healthy.

The weekly occurrence of epizootic and epidemic plague in Newcastle is shown hereunder :—

Table 28.

Rodents

Number

Human Cases

Examined.

Infected.

Notified.

April 1 . . ..

300

10

3

8 .. ..

310

14

1

15 . .

275

4

22 .. ..

314

17

29 .. ..

279

9

1

May 6 .. ..

046

23

3

13 .. ..

664

20

1

20 .. ..

616

42

27 .. ..

729

33

3

June 3 .. ..

518

22

10 .. ..

393

2

1

17 .. ..

454

7

24 .. ..

209

July 1 .. ..

163

1

8 . . . .

245

2

1

15 .. ..

143

22 .. ..

78

29 .. ..

118

August 5 . . ..

122

12 . .

44

19 .. ..

33

Though more than 2,500 rats caught in the suburbs of Newcastle were examined, only five were found to be infected with plague. Four of these were taken from a garbage tip, at which two cartloads of refuse from an extensively infected building were surreptitiously deposited. This happened on 6th May, 1905; four plague-infected rats were discovered at this tip between 12th June and 15th June, 1905. The other infected rat was caught on 31st May at a stable where a large consignment of chaff had been delivered from a badly infected premises in Newcastle. At this stable six other putrid carcasses were discovered.

Dick, in his account of this Newcastle epidemic, comments upon the .relation between epizootic and epidemic plague as follows:—

“ Consideration of the subject of plague in rats, and its relation to plague in man, shows on the one hand that at 41 different premises in the city (excluding the wharfs) which yielded plague rats, no cases of plague occurred amongst the occupants or employees of any of these premises. A premises may apparently he grossly infested by plague rats, and yet no case occur amongst the inmates of those premises. On the other hand, in the thirteen cases 4 of plague (one case being excluded), infected rats were discovered at the residence or place of employment of eleven out of the thirteen cases.” In the other two cases there was good reason to believe in the probability of incidental exposure within the limits of an infected area.

Origin of the Epizootic Infection in Newcastle.

“ Little consideration need be given to the question whether the disease was introduced into Newcastle by means of ships from plague-infected places in other parts of the world. Never at any time has there been a history of plague infection in man or rats on board any ship reaching Newcastle from any foreign port. Newcastle is in daily communication with Sydney by rail and sea, the trade between the two cities being very considerable by both routes. Frequent communication is maintained by sea between Newcastle and the northern ports in this State, as well as with Brisbane and other ports in Queensland.

Epidemics of plague were experienced in Sydney during 1900 and 1902, and occasional cases occurred in 1901, 1903, and 1904, whilst plague-infected rats were found there, especially about the harbour frontages, during each succeeding year since 1900.

“In Brisbane plague has not been absent since 1901.

“ There has been no positive evidence that plague in rats or man reached Newcastle by means of vessels trading with any of the above-mentioned places.

“ All that can be definitely stated in reference to the source of infection of the Newcastle outbreak is this: At several State and inter-State ports with which Newcastle was in direct and frequent communication by sea, as well as by land, cases of plague in rats and man existed for several months prior to the occurrence of the first case of plague in Newcastle; that produce and other goods were shipped direct from these ports to produce stores in Newcastle; that, after the notification of the first case of plague, on 25th March, search of the produce store at which the patient worked resulted in the finding of a number of plague-infected rats, and the carcases of a large number of dead and putrid rats which had apparently succumbed some weeks previously. That similar conditions, as regards rats, were met with on other premises in the city. That, as soon as search was made, plague-infected rats were found about the wharfs, where vessels from the places referred to above lay, and infected rats continued to be taken about these wharfs down to 6th July, 1905.

“ The inference drawn from these circumstances is, that the infection was transported to Newcastle, either by produce infected by means of plague rats, and conveyed from it to the local rats, or what is much more probable, that rats were transported, and landed at Newcastle, and, in turn, communicated the disease to the local rodents, and, from them, to human beings.”

Inasmuch as Dick lays so much emphasis on produce in connexion with the origin of this outbreak, and as the commencement of the outbreak is so definitely associated with a known focus in a produce store, it is unfortunate that no record seems to have been kept of the places from which that store had received consignments of produce within the period preceding the assumed date of the onset of the epizootic outbreak in the produce store. This information, if adequately analyzed, and followed up, might have produced evidence of great value in connexion with the epidemiology of plague in Australia.

1907. Kempsey.—The first human case of plague at Kempsey occurred on 23rd January, 1907. This patient had been employed in a produce store, where, on 16tli and 17tli January, he had assisted at the removal and destruction of 31 dead rats which were found beneath one of the floors. Many vague statements were rife as to rats having been unusually numerous in Kempsey in the latter part of December, 1906, and the beginning of January, 1907, but no rat mortality appears to have been observed until the finding of the 31 dead rats at the produce store. As soon as the diagnosis of the first case had directed attention to the matter, definite evidence was obtained of epizootic plague in the Kempsey rats. On 29th January was found a dead rat which was probably plague-infected. The last infected rat was found on 18th Kebruary, and, altogether, seven premises were found to be harbouring infected rats, infection being positively demonstrated in twelve rats from these places, and on some other premises evidence was obtained of previous rat mortality. A total of 511 rodents was examined.

As to the source whence the infection was carried to Kempsey, there can be little doubt that it was carried from Sydney in produce or other merchandise. The owner of the produce store received frequent consignments of horse-feed from Sydney. His books showed that in the month of December, 1906, he had received 393 bags of chaff from produce merchants in Sussex-street. Sydney. Infected rats were taken at the Federal wharf, which is in the vicinity of the premises whence the chaff was supplied, on 19tli November, lltli December, and 12th December. The finding of infected rats at the North Coast Steam Navigation Company’s Kempsey wharf on 17tli and 18th February may probably be accepted as a further indication of the path by which the infection was conveyed to the produce store. [Millard: Plague at Kempsey, p. 30.]

CHAPTER XI.—EPIZOOTIC PLAGUE IN QUEENSLAND.

Epizootic Plague in Brisbane.

The first record of plague in rats in Brisbane was on 5th March, 1900, when one rat was found dead in a shop close to a wharf at which vessels from Sydney had recently arrived. On examination this rat was found to he infected with plague. The first plague case in man occurred on 27th April. It is assumed by Ham (page 3) that the infected rat found on 5th March marked the commencement of the epizootic in Brisbane. Inquiry of wharfingers and officials whose business took them to the wharves elicited the information that an unusual fatality among rats had taken place prior to the occurrence of the first case in man on 27th April. After reviewing the evidence Ham concludes that “the above facts support the opinion that the disease was introduced by plague-infected rats from Sydney, and that the infection spread to the local rats, which in turn communicated it to man. The last case of plague in man in Brisbane during 1900 was reported on the 13th December, 1900; the last infected rat on 24th October, 1900. The total number of rats examined in this year was 735, the number identified as infected, 90.

1901. —In this year no infected rats were found in January, February or March, the first being found infected on 4th April. The last-infected rat was found on 22nd November, 1901. During the year, 1,851 rats were examined, of which 101 were found to be infected.

1902. —The first infected rat was found in the third week in January, the last during the second week in August. The total examined was 3,851, of which 106 were found to be infected.

1903. —The first infected rat was found in the second week in January, the last on 28th September. A total of 14,361 rodents was examined, of which 88 were found to be infected.

1904. —The first infected rat was found on 8th January, and the last on 15th December. A total of 25,653 rats and mice was examined, of which 404 were found to be infected.

1905. —The first infected rat in this year was found on 4th January. The last infected rat was found on 29th November. With the exception of one infected rat on the 4th July, and one on the 29th November, there was no plague in man or rats from July to December. A total of 16,780 rodents was examined, 129 being found to be infected.

1906. —The first plague-infected rat was found on 12th January, and the last infected rat on 28th December. A total of 12,195 rodents was examined, of which 48 were infected.

1907. —The first infected rat was found on 2nd January, and the last on 20th December. A total of 19,610 rodents was examined, of which 45 were infected.

1908.    The first infected rat was found on 22nd January, and the last on 15th September. The total rodents examined was 20,426, of which 71 were infected.

1909. —During this year a total of 27,828 rodents was examined, none being found infected within the metropolitan area.

This was the last year in which epizootic plague is known to have occurred in Queensland.

The monthly statement of infected rats identified in the metropolitan area of Brisbane is as shown in the following table:—

Table 29.

Year.

in

c3

0

►"5

1

5

3

March

£.

%

►-5

>>

tri

<

-O

ft

m

1 ;

_ ! 1 r g

o > 3 o O «

M

1

Total.

1900

5

3

15

21

24

15

7 . .

90

1901

16

23

32

20

8

1

1

101

1902

3

6

7

53

16

12

8

1

106

1903

1

8

30

20

15

6

4

84

1904

21

3

25

25

89

150

38

17

4

6

2

380

1905

5

59

48

3

7

5

1

. . 1

129

1906

1

6

6

3

5

6

2

8

1

10

48

1907

4

6

1

5

3

3

4

6

5

2 5

1

45

1908

21

1

17

11

14

2

5

71

1909

Total ..

35

1

109

123

128

175

240

108

66

34

10 13

13

1,054

Extra-Metropolitan Epizootic Plague in Queensland.

Rockhampton, 1900-1906.—Human cases occurred at Rockhampton, in the separate years 1900, 1903, and 1906. The sequence of events associated with the presumed introduction of infection into Rockhampton is as follows:—On 16th April, 1900, s.s. Burwah had arrived from Sydney via Brisbane, carrying passengers and cargo. On 17th April, the head steward was reported as suffering from plague, having fallen ill on 15th April. The ship was moved from the wharf to the quarantine anchorage on discovery of the condition of the steward. On the removal of the lining of the cabin occupied by the steward, several dead rats were found. On 20th April, a waiter at the Criterion Hotel, Rockhampton, who, in the course of his hotel duties, boarded all passenger steamers arriving at Rockhampton, was first attacked with plague. In a report dated 8th May, Dr. Turner reported that “ the head wharfinger informs me that rats have not been numerous about the wharfs. Notwithstanding this, about a fortnight ago, he observed (what he had never observed before) four or five dead rats lying about the wharfs every morning for three consecutive days. After this he found two rats daily, the last being found five days ago.” Up to 15th June, 1900, 25 cases had occurred at Rockhampton, and it had then been •well established that an epizootic existed among the rats of the city.

A study of the above sequence of events makes clear that the s.s. Bunvah was infected prior to arrival at Rockhampton, probably at Sydney, and contained on arrival at Rockhampton a fully-developed epizootic of rat plague, transmitting infection to one human resident, and to the local rats of Rockhampton.

Ham records that in 1903 “infected rats were found at Rockhampton.” “ After an absence of six years, plague in epidemic form reappeared at Rockhampton on 3rd April, 190G. There is good reason to believe that infection Avas imported by rats from Aressels arriving at the toAvn wharfs.” This statement by Ilam (page 16) appears to ignore the tAvo human cases Avliicli occurred in 1903, and no evidence is given for discarding any hypothesis that epizootic plague had persisted in Rockhampton through the six years, or in support of the statement that plague had been re-introduced. It is stated that eight of the eleven cases Avere directly connected Avitli one Avareliouse, and all eight cases were reported Avitliin a period of eight days. It Avas ascertained that dead and diseased rats had been found in the Avareliouse premises just prior to the outbreak. Dead rats had also been found in a store adjacent to the Avareliouse.

During 1907, 6,982 rodents from Rockhampton, and, during 1908, 1909, and 1910, a total of 7,210 Avere examined, Avitliout any infected rat being identified.

Townsville, 1900-1907.—Human cases of plague occurred at ToAvns-ville in the separate years 1900, 1902, 1903, 1905, 1907.

On 27tli April, 1900, a steAvard on board s.s. Cinlra Avas reported as suffering from plague. The patient had been taken ill on 20tli April, the day on Avliicli the vessel had left Sydney, and had been ill on the vessel Avliile the latter Avas at Brisbane on 22nd and 23rd April.

No further information is aAmilable concerning subsequent eA'ents at ToAvnsville.

Ham states (page 9) that “ infected rats Avere found at ToAvnsville during 1903. During the twelve months ending 30tli June, 1901, 28 rodents Avere found to be infected. In 1905, 63 plague-infected rats were discovered at the jetty Avliarf. Of 489 rats examined at ToAvnsville during October, five Avere found plague-infected. The last infected rat in 1905 Avas found there on 6tli October.

During the year 1907, 3,007 rodents Avere examined, none of Avliicli Avas found to be infected.

During 1908, 724, and, during 1909, 5,353, none being identified as plague-infected. In 1907, a fatal case occurred at ToAvnsville on l7tli March. This patient Avas also employed in a produce store Avliere dead rats were subsequently obtained.

u

Cairns.—Human cases of plague occurred at Cairns in the separate years 1900, 1903, 1901, 1905, 1906, 190S. There is no record concerning rodent plague at Cairns until 1903, when it is stated that “ infected rats were found at Cairns.” In 1905, a man employed as a rat-catcher contracted plague at Cairns during the month of June. Early in the same month two dead rats had been found at Cairns with naked-eye evidence of plague. During the year 1906, ten cases of human plague occurred at Cairns, and, consequently, the town of Cairns was thoroughly cleansed, and a vigorous crusade carried on against rats. Although active search for rats was continued during and after the outbreak, comparatively few rats were found in the town. One rat, dead of plague, was found on the premises where one human case had occurred ten days previous to the onset of illness. The number of rodents examined at Cairns during 1907 was 246, of which 60 were found to be infected. In 1908, 126 were examined, of which 34 were infected. In 1909, 278 were examined, none being infected.

Bunclaberg.—Human cases occurred in the years 1902, 1903, 1905, but the total cases for the three years was only 4. In 1903, infected rats were found. In 1907, 590 rodents; in 1908, 243; and in 1909. 1,180 rodents were examined, none being infected.

Childers.—In this small town, approximately equidistant between Bundaberg and Maryborough, one human case occurred on 16th May, 1905. Large numbers of rats were found dead in the town, the epizootic being severe. Circumstances seemed to indicate that infection was conveyed by fodder from Bundaberg. After vigorous sanitary measures no further human or rodent plague was identified.

Maryborough.—Human cases of plague occurred in this town in 1904, 1905. The first human case in 1905 fell ill on 19th. May, the patient being a boy employed in a fruiterer’s shop, beneath and alongside of which ran an open sewer which afforded an excellent harborage for rats. A careful search for rats at the time in the vicinity of this sewer elicited no evidence of plague infection among the rodents, which, however, were found in large numbers. During the cleaning of the town, 266 rodents were examined, only two being found to be infected. There is a discrepancy in Ham’s report with regard to rodent plague. On page 59, it is stated as above that two rats were found to be infected, while on page 49 it is stated that a subsequent search for rats in the vicinity of the infected house, and about the town in general, revealed no evidence of plague infection among the rats.”

Ipswich.—Human cases of plague occurred at Ipswich in the years 1900, 1904, 1905, 1907. In 1900 and 1904, there occurred only one case each year. In 1904, infected rats were found at Ipswich. In 1905, on 4th May, one human case of plague was discovered. Within a week six other cases occurred. All of these cases were traced directly to a produce store, a dilapidated shed in which rats had been reported to be dying in large numbers a week before the outbreak.

No further information with regard to Ipswich is available.

Port Douglas.—In connexion with the epidemic of plague at this place in 1907, no information is available as to the occurrence of rat plague.

Machay.—Following the occurrence of two human cases, one in January and one in June, 1909, intensive inspection and rodent destruction measures resulted in the discovery of five positive smears amongst 1,358 smears of spleen blood examined from rats obtained at Mnckay during the months of July, August, and September, 1909.

C.5769.—3

CHAPTER XII.-EPIZOOTIC PLAGUE IN VICTORIA.

Although there occurred eleven local human cases of plague in Victoria—ten in 1900, and one in 1902—there is no reference in the published official reports to plague amongst rats in Victoria. By the courtesy of Dr. Robertson, Chairman of the Health Commission of Victoria, I am enabled to publish the following brief records of epizootic plague

5th March, 1900.—Reported to the Board that “ many plague rats had recently been found about the wharfs.”

7th March, 1900.—Plague rats found in a store in South Melbourne.

11th March, 1900.—Plague rats found in a bag store in Plinders-street.

30th May to 22nd June, 1900.—Plague rats found on wharfs.

29th August, 1903.—Plague rats on s.s. Syrian from Queensland. Of 158 dead rats found after disinfection one was shown to be infected.

30th September, 1903.—Plague rats on Margaretha. from Buenos Ayres. With reference, however, to this entry it is elsewhere stated that a number of dead rats were found after disinfection of the vessel. The presence of rat plague was not proven.

CHAPTER XIIL-EPIZOOTIC PLAGUE IN SOUTH AUSTRALIA,

1900.—Human cases of plague occurred during January, 1900. In that month plague was identified in rats during the same month, three infected rats having been found at the Adelaide Hospital, and one in one of the main streets of the city of Adelaide.

In connexion with the 1909 cases of plague at Port Adelaide, plague-infected rats were found in the locality involved. The exact number is not known, but the last infected rat was found on 19th June, 1909.

CHAPTER XIV—EPIZOOTIC PLAGUE IN WESTERN AUSTRALIA.

1900. —In the first year of epidemic plague there is no mention of rat-plague. In one of the infected premises (case 5) “there was ample evidence of the ravages of rats or mice.”

1901. —In this year it is recorded that one of the cases from Fremantle (case 13) “visited Perth with goods, and went to various shops in the rat-infected area there.” From the available records which are incomplete, it appears that infected rats were found in several parts of Perth, but the actual number is unknown.

1902. —Three human cases, which occurred at Fremantle, had an interesting relationship to previous cases of plague. The oificial report says—“ Two years ago cases of plague occurred in the restaurant situated next door to the present cases’ residence; another case occurred in a man working at a warehouse situated 70 yards away, whilst in another house, 80 yards awray, a case occurred twro years and three months ago, this being the first case in Fremantle (1900). On 3rd June two plague-rats were discovered at the flour mill where case 1 worked.”

1903. —During the outbreak in this year (January and February) the first infected rat this year was found on 2nd February—nine days after the first case had occurred, and after 30 rats had been examined. During the outbreak 471 rats were examined, and 99 of them found infected. The worst rat infection appears to have been during the week ending 15th March, 1903, when, of 65 rats examined, 29 were infected. Infected rats “were still being found on 24tli March, 1903.” (Official Deport on Plague.) Between that date and 4th April, 65 rats were examined, two being infected. During October, 1903, plague-rats were discovered in Perth.

The official records are not complete, but it is evident that, in addition to the rats recorded above, which came from Fremantle, a total of at least 1,786 rats from Perth were examined, of which 297 were infected.

1904. -—The first human case of plague occurred in Perth on 20th June, 1904. Blackburne, in his official report, states: “I have found no infected rats since about 20th March last.” That statement refers to Perth. With regard to Fremantle, the first human case occurred on 28th July, the last infected rat having been found there on 21st March. Infected rats were found at Perth on 17th May, and at Fremantle on 16th May. No further reliable information is available for this year.

1906.—Human cases occurred this year between January and May. The epizootic evidently accompanied the epidemic, although detailed information is not available. It is clear that rat-plague continued after

human plague, as plague-rats were found during June. The following is a tabulation (incomplete) of the results of rat examination from February to June, 1906:—

Table 30.

Week Ending.

Perth.

Fremantle.

Examined.

Infected.

Examined.

Infected.

Feb. 17 .. ..

?

Nil

V

Nil

24 . . ..

?

?

9

?

March 3 . . .

71

4

120

5

10 .. ..

165

41

93

17 . . . .

113

5

133

24 .. ..

63

1

123

7

31 . . . .

53

72

April 7 .. . .

49

71

14 .. . .

35

84

3

21 .. ..

20

I

49

28 . .

30

52

May 5 .. ..

23

49

12 .. .

30

72

19 . .

20

32

26 .. . .

l 43

60

June 2 .. ..

/

9 .. ..

23

21

2

16 . . . .

t 22

29

2

23 .. .

1

30 .. . .

11

47

/

CHAPTER XV.—EPIZOOTIC PLAGUE IN TASMANIA.

Epizootic plague lias never been recorded in Tasmania. On the outbreak of plague in Australia in 1900, a joint committee to supervise all measures for the destruction of rats was formed. Between May, 1900, and 31st October, 1900, a total of 13,993 rats destroyed was confirmed, and it is estimated by the Board that 20,000 represented more accurately tbe number killed. Work was recommenced on 25tb March, 1901, and suspended on 28th September, 1901. Within that period, 15,878 rats had been destroyed and accounted for.

As far as can be ascertained, no measures were taken to ascertain whether any of these rats was plague-infected. The numbers destroyed in the years 1902 and 1903 are not recorded. In 1904, some 15,500 are known to have been destroyed. During the official year 1905-6, organized rat destruction operations were discontinued. In the official year 1906-7 Elkington reports: “ A number of rat carcases have been examined in the laboratory for traces of plague, but without result.” This is the first reference to any laboratory examination of rats.

1900.

Burwah.—This vessel, carrying passengers and cargo, left Sydney on 10th April, 1900, and called at Brisbane, which port was left on 13th April. On 16tli April the vessel arrived at Rockhampton. On 17tli April the head steward was found to be suffering from plague, having been taken suddenly ill on the evening of 15th April. On removal of the lining of the cabin occupied by the patient, several dead rats were found. It is presumed in the official reports that an hotel runner, who developed plague on 20tli April, was also infected from this vessel. No further details are available with regard to this vessel.

Cinira.—This vessel left Sydney for Queensland ports on 20th April,

1900,    called at Brisbane and remained there on 22nd and 23rd April, and arrived at Townsville about 27tli April. On this date a steward on the vessel was found to be suffering from plague. The patient first became ill on 20tli April, the date on which the vessel left Sydney. No further information is available.

South Australian.—At the end of April, 1900, a case of plague was discovered on the s.s. South Australian on her arrival at Melbourne from Sydney. The patient was a fireman, whose infection was traceable to Sydney. (N.S.W. P.R., 1900, p. 32.) No other details are available.

Nera.—The s.s. Ahera, from Colombo, was quarantined at Fremantle on 22nd May, 1900, on account of plague. No details are available. The agents of the vessel contested payment of expenses, maintaining that the case was not plague.

Cerberus -—One case of plague was discovered on II.M.S. Cerberus at Melbourne, but, as this vessel was a store-ship at permanent moorings, it is probable that this case should properly be regarded as a shore case.

1901.

Antillian.—This vessel was a chartered troopship, which left Cape Town on 1st February, 1901, in ballast, and carrying no cargo. The vessel had a crew of 65, and no passengers. The vessel arrived at Albany on 20tli February, anchored in stream, and took coal from a lighter, leaving Albany on 22nd February. On arrival at Sydney on 2nd March,

1901,    an able seaman was reported as being ill, and his illness was determined to -be plague. This patient had become ill on 27th February. On lltli March another member of the crew, a storekeeper, became ill with plague.

On 2nd March the putrid carcase of a rat was found on the vessel; on 4th March the bodies of two other rats were found, both of which were identified as being plague-infected. The master of the vessel stated that there had not been many rats on board the vessel; but that, on the

day of departure from Albany (22nd February), some unusual, though not great, mortality had been discovered, about fifteen carcases having been found and thrown overboard.

In view of the fact that plague had occurred in South Africa, the Antillian had been placed under fumigation with sulphur almost immediately on arrival at Sydney. After the diagnosis of the first case had been established, the vessel was submitted to a second fumigation, which began on 3rd March, and continued till the morning of 4th March. Neither of these fumigations can have much affected the storerooms, since they were separately built up within the forward compartment. On 5th March the storerooms were inspected preliminary to directing special disinfection, and the carcases of one putrid and one desiccated rat were then found. The rooms and their contents were thoroughly sprayed with sublimate solution, 1-500, by the quarantine staff, and afterwards were fumigated with burning sulphur. On 9th March the stores were transferred to a lighter under the direction of the storeman (who was the second case), so that the rooms might be more thoroughly cleansed. During this removal ten more carcases were found. After the cleaning the stores were replaced on 11th March—again under the supervision of the storeman. The latter, who had not been on board except on the dates mentioned, fell ill during the night of llth-12th March. It is, therefore, most probable that he was infected on 8th March, during removal of the stores. Several other persons were engaged in this work, none of whom fell ill. The rats taken from this vessel were all Mus decumanus.

There is an important statement by Thompson in his account of the outbreak on this vessel. Writing under date 31st July, 1903, Thompson says: “ The Antillian is the only vessel entering the port of Sydney on which either plague-rats or cases of plague in man have been discovered.”

1902.

Eulomene.—The four-masted barque Eulomene left Liverpool on 12th October, 1901, carrying a crew of 34, and a general cargo. She arrived at Sydney 15th January, 1902, without evidence of plague during the voyage. She lay in the stream until 21st January, when she went alongside Federal Wharf and discharged cargo. On 26th February she left Federal Wharf and lay in the stream till 6th March. On 6th March the vessel was fumigated, after which process the holds were searched for dead rats, many fresh carcases being found, altogether about 40 being found and thrown overboard, none being examined. On arrival at Newcastle on 7th March, the Eulomene went alongside, discharging cargo and taking in coal. On 20th March the vessel moved to permanent dolphin moorings. On 17th March the ship’s steward was taken ill with plague. On confirmation of this case, a further fumigation was carried out, and a very thorough search for rats was made. About 20 desiccated carcases were found, but only two recently-dead rats and one mouse; the latter, on examination, showed no evidence of plague.

The patient, who, as ship’s steward, was responsible for obtaining the ship’s stores, stated that he had obtained, while the ship lay at Sydney, fresh meat and vegetables from the ship’s butcher ashore. A bag or two of potatoes were supplied at a time, and were left on board in his store; on several occasions, on putting his hand into the bags, he encountered rats which were stupid and sluggish, and were easily destroyed. He said that he had thus found six rats at least, on different occasions, and for the last time some few days before leaving Sydney.

Thompson, in discussing the circumstances of this case, canvasses the alternatives in detail—

“ It is quite possible that at some time or other before 5th March, during the Eulomene’s stay there, the Federal wharf may have harboured plague rats, of which specimens were secured from other wharfs at no great distance. The ship’s rats may also have become infected during her long stay at a wharf in an infected neighbourhood in other ways, as exemplified by the steward’s account, which latter seemed trustworthy as regarded the important points. Secondly, after the first fumigation at Newcastle, 20 desiccated carcases of rats were found. The one person infected in this instance was the steward, and, according to his account, he had been specially exposed. Was he infected directly from the sick rats he took out of the potato bags? This cannot have been the case, because he was not attacked until ten days after he had left Sydney, and the last occasion on which he had caught a rat was several days, as he said, before leaving. For similar reasons he cannot have been otherwise infected at Sydney, for he had not been ashore there for nine days before he arrived at Newcastle, or nineteen days before his attack; and he was not infected on shore during his stay at Newcastle, because there had never been plague there, and the only case which occurred at Newcastle (see p. 17) was not attacked until 7th August, or five months afterwards.”

It seems clear that there had been an epizootic of plague on the vessel, the infection of the ship’s rats being traceable to Sydney, and that the steward was infected from these rats.

Paroo.—The shipping inspector at Fremantle reported on 5th June, 1902, as follows“ Soon after the arrival of the Paroo (an overseas vessel trading from Singapore) on her last trip here, I heard that rats were dying all over the ship, and after some trouble was enabled to get possession of six or seven of them, which I delivered to the plague medical officer at once.” No further information is available concerning this incident.

1903.

Alsterschwan.—The barque Alsterschwan left Tacoma, Washington, on 18th September, 1902. From Tacoma the vessel went to Callao (14th December), Buenos Ayres (4th March), Rosario (17th April), Buenos Ayres (1st June), whence she sailed on 1st June for Sydney, arriving

at that port on 29th July with a crew of 26, no passengers, and a full cargo of maize m bags. USTo sickness was reported on board. From 29th July until 3rd August the vessel lay at anchor in Sydney Harbour, going alongside a wharf at Darling Island on the latter date. On 3rd August one of the crew offered 112 rats at the public depot. This fact was at once reported, and investigations made. It was learned that these rats had been found dead near the ventilators in the holds as soon as the hatches were removed. The Health Department staff commenced operations on the ship, and on 4th, 5th, 6th and 7th August delivered 1, 9, 25, and 16 rats, all of which were examined in the laboratory. Two of the sixteen were found to be plague-infected. Nine other infected rats were found subsequently. During the emptying of the ship 117 carcasses were discovered in various parts of the vessel, but no live rats were seen. No further incident occurred in connexion with this vessel.

The Alsterschwan was the second vessel on which plague-rats had been detected in Sydney. All of the rats found on this vessel were Rattus alexandrinus.

Innamincka.—The Innamincka, a coasting steamer of 2,500 tons, was trading between Melbourne and Northern Queensland ports. This vessel had arrived at Sydney from Melbourne on 27th August, 1903, and had left Sydney on 29th August. The vessel arrived at Brisbane on 31st August, leaving again on 1st September. On 3rd September an able seaman fell ill, and on arrival of the vessel at Townsville, Queensland, on 4th September, the illness was diagnosed as plague, and the patient was removed to hospital, where he died on 6th September. No other case occurred, and there was not at any time evidence of rodent plague on the vessel.

Thompson (P.R., 1903, p. 9), in discussing this case, says: “Three sources of infection lay open to the patient, therefore; these were Sydney wharfs, the vessel itself, and Brisbane. Melbourne wharfs were under no sort of suspicion then or later, and may be safely excluded. Nothing at any time appeared pointing to infectiveness of the vessel, so that choice lay between Sydney and Brisbane.” Thompson, after discussing the incubation periods in the alternative possibilities of infection at Sydney (156-108 hours) and at Brisbane (59-35 hours), concludes: “ A decision as to the place at which the patient was infected is, of course, not possible; but, in my opinion, the balance of reasonable probability inclines to Brisbane.”

Sultan.—One case of plague was landed from this vessel at Fremantle on its arrival from Singapore. No further details are available.

Lingard.—Two cases of plague were landed from this vessel at Fremantle on its arrival at Bunbury from Africa. No further details are available.

Pilbarra.—A steward from this vessel was removed to hospital for observation at Fremantle on 3rd June, 1903, but was discharged three days later. An examination of ten rats found dead on this vessel on 29th May, 1903, showed five to be plague-infected “ very severely.” The Pilbarra had been in Sydney on 17th April, from whence she had travelled to Fremantle, thence to Melbourne, and returned to Fremantle, when the infected rats were discovered. The New South Wales authorities, in correspondence with the Western Australian department, suggested the probability of infection of the vessel having occurred during the stay of the vessel at Fremantle on 30th April.

Amongst the cases of plague occurring at Fremantle in 1903, one patient (No. 7, vide p. 103) was by occupation, a “ ship’s steward.” He was a resident of Fremantle, and there is no evidence available as to the source of his infection.

Syrian.—For details of this vessel, see page 66.

1904.

Meeinderry.—On the arrival of this vessel, a coastal steamer, at Geraldton (Western Australia) on 28th July, 1904, one of the crew was found to be suffering from plague. This patient had been living at Fremantle and working on the wharf there until 26th July, and the conclusion officially accepted was that the patient had been infected in Fremantle before joining the vessel.

Illawarra.—On 10th May (?), 1904, plague-infected rats were found on this vessel, a coastal steamer, at Sydney. The information in respect of this vessel is incomplete.

Hobart.—On the arrival of this vessel, a coastal steamer, at Fremantle, on 22nd March, 1904, from Sydney, a plague-infected rat was reported as having been discovered on board, but it appeared later that the rat was discovered in the shed on the wharf at which the Hobart had been berthed. The rat was discovered after cargo had left the ship, and it was only presumed, but not established, that it came from the vessel. At this date plague-infected rats were being found in Fremantle.

1905.

Ville de la Ciotat.—The French mail steamer Ville de la Ciotat, from Noumea, was quarantined at Fremantle on 15th November, 1905. This vessel had left Noumea on 17th October for Europe, via eastern ports of Australia and Fremantle. Between 17th October and 1st November about eleven dead rats were discovered on board, but no particular attention was paid to this, although unusual on this vessel. Four cases of plague developed on board, one fireman (H.N.) on 12tn November and a fireman (G.) and sailor (Mi.) on 13th November. One other case (Mw.) developed, concerning which no records are available. The vessel was handled in quarantine at Fremantle, passengers and the four cases being landed into quarantine, mails and cargo lightered and fumigated at a buoy, and coaling carried out by tbe ship’s crew from hulks alongside. Of the four cases landed. Mw. died of pneumonia on 21st November, and Mi. of pneumonia shortly afterwards. The other two cases recovered.

1906.

Aramac—On 9th and 10th February, 1906, five plague-infected rats were found on board the coastal steamer Aramac on her arrival at Brisbane from Sydney, and before berthing at the Brisbane wharf. There is no evidence to show how these rats came to be sought for or discovered.    -

Bega.—On 15th June, 1906, a donkeyman fell ill on this coastal steamer whilst at sea. Less than a week previously he had handled two dead rats on board. He landed at Sydney on 19th June and died suddenly from a fulminating pneumonia on 23rd June. His wife and an attendant neighbour subsequently died from pneumonic plague. Investigation showed no signs of infected rats on the vessel. (P.R., 1906, p. 7.)

1907.

Arawatta.—On 17th May, 1907, a case of plague was reported from the Melbourne Hospital. The patient was a steward from the s.s. Araiuatta which had arrived in Melbourne the previous day. The crew were at once placed under close surveillance, and arrangements were made for the disinfection and sulphur fumigation of the vessel. The rats killed by the fumigation process were examined, and found to be free from plague. No further case occurred. The vessel was trading between Melbourne and Queensland ports.

Mareeba.—On 16th September, the Mureeba arrived at Brisbane, and a steward, aged 47, was found to be ill with plague. The vessel was a cargo vessel trading between Sydney and Rockhampton via Newcastle and Brisbane. The patient was first taken ill on the 12th, when the vessel was at Newcastle, bound for Sydney. He was seen in Sydney by a medical man, but was not considered to be suffering from plague. After fumigation of the vessel, a thorough search far rats was made, all the linings and ceilings were pulled down, and a number of rats in various stages of decomposition were found, several dead rats being found amongst the provisions in the food lockers. “ During this work, 68 rats and 10 mice were found; 42 of the rats (probably plague-infected) were too decomposed for examination, and of the remaining 26 rats and 10 mice none was found infected. All the rats on the vessel were Mils alexandrinns itifus. All circumstances point to the ship as the source of infection.” (Ams. Med. Gaz1907, p. 539.)

1909.

“ Two cases of plague were imported into the Port of Bunbury by a vessel seventeen days out from Bombay and Madras. The patients recovered, and fumigation of the vessel resulted in 40 rats being found, of which seven were infected with plague.” (Ann. Rep. Health Dept., 1909, p. 17.)

Table 31.

Summary of Vessels on which Plague or Suspected Plague

Occurred, 1900-1909.

Vessel.

Year.

Source of Infection.

Human Infection, Number of Cases.

Rodent

Infection.

Class or Rating of Patient.

Burwah

1900

Sydney ..

2

Positive

Head Steward, Hotel Runner

Cintra

1900

Sydney . .

1

Unknown

Steward

South Australian

1900

Unknown

1

Unknown

Fireman

Nera ..

1900

Unknown

9

Unknown

Unknown

Antillian

1901

Africa

2

Positive

Able Seaman, Storekeeper

Paroo. .

1902

Unknown

Nil

Probable

Eulomene

1902

Sydney ..

1

Positive

Steward

Sultan

1903

Singapore?

1

Unknown

Unknown

Lingard

1903

Africa

2

Unknown

Unknown

Pilbarra

1903

Unknown

Nil

Positive

Alsterschwan

1903

South

America

Nil

Positive

Innamincka

1903

Sydney or Brisbane

1

Negative

Able Seaman

Syrian

1903

Sydney or Brisbane

Nil

Positive

Meeinderry

1904

Fremantle

1

Unknown

Unknown

Illawarra

1904

Unknown

Nil

Positive

Hobart

1904

Unknown

Nil

Doubtful

Ville de la Ciotat

1905

Unknown

4

Probable

2 Fireman, 1 Sailor, 1 Unknown

Bega .

1906

Sydney . .

1

Doubtful

Don key man

Ararnac .

1906

Unknown

Nil

Positive

Arawatta .

1907

Unknown

1

Negative

Steward

Mareeba ■.

1907

Unknown

1

Positive

Steward

Redbridge .

1909

India

2

Positive

Unknown

St Louis .

1909

2

Fireman, Boatswain,

The most striking fact wliicli appears from a compilation of the records relating to plague on shipboard in Australia is the extreme paucity of the information which has been preserved. Even on official files material information of the first order of epidemiological importance has not been recorded. Alone amongst those concerned with plague at the time, Ashburton Thompson had realized that the conditions existing on board various types of mercantile vessels offer most favorable opportunities for obtaining most valuable evidence in respect of some phases of the behaviour of a disease like plague; and Thompson has left on record the most complete and detailed account of the circumstances in the case of each vessel on which plague occurred within his jurisdiction.

The number of cases which occurred on any vessel is small; with the exception of the French mail steamer Ville de la dot at, on which there were on arrival at Fremantle four cases, there were not more than two cases on any vessel.

A total of 21 vessels were dealt with during the ten years of epidemic or epizootic plague in Australia. Of these six (Antillian. Paroo, Sultan, IAngard, Alsterschwan, and Redbridge) were certainly, or most probably, instances of direct importation from overseas. Of the Ville de la

Ciotat nothing more can he said than that the vessel came from Noumea, via Sydney, and that plague existed at both places. The precautions which were then being taken at Sydney might be taken into consideration in arriving at a judgment, but the information is altogether too scanty to warrant any definite statement.

Five of the vessels (Neva, Illawarra, Hobart, Bega, Aramac) must be dismissed from further consideration as the information available is too incomplete for discussion. Concerning the Cintra and the South Australian, all that is known is that one human case occurred on each vessel, and, that, according to Thompson, the infection in the case on the South Australian was traceable to Sydney.

Three vessels (Innamincha, Meeinderry, Arawatta), and probably also the South Australian, were instances of vessels acting as carriers of human cases infected at some point external to the ship. In each case there was no evidence of the rats on the ship being infected, or of the ship being in any way a focus of infection.

The Pilbarra was an example of a vessel on which rodent plague was demonstrated, without the occurrence of a definite human case of plague. The Alsterschwan was another striking instance of a ship epizootic without a ship epidemic.

The Burwah, Mareeba, and Eulomene were cases in which epizootic and epidemic plague were co-existent. Of the human cases concerning which anything is known, and excluding the hotel-runner from the shore, allegedly infected on the Burwah, six were stewards or storekeeper, two were able seamen, and one was a fireman. One of these seamen and the fireman were infected ashore. This exceptional incidence upon one section of the crew is merely an expression of the greater personal risk involved in handling of ship’s stores and food materials, these materials attracting rats to those portions of the ship where the stewards and storekeepers work.

This group of ships on which plague was identified offer interesting examples of the three types of vessels which are liable to require treatment during an epidemic or epizootic of plague.

(a)    The vessel on which there has occurred a human case of

plague, the human case having been infected before joining the ship, or whilst ashore at some port of call.

(b)    The ship on which there occurs an established outbreak of

plague amongst rats, without the infection of humans on board. The barque Alsterschwan was a most striking instance of this kind, an extensive and apparently severe epizootic being unaccompanied by any human case.

(c)    The ship on which plague has occurred amongst rats, and on

which human cases have also been identified. It is ot -    some importance to note that in the case of every vessel

in the present series, which fell within this group, the first intimation of plague either in man or rats was given

by the detection of the human case. This is necessarily so in the case of the detection of a human case on the arrival of a vessel from oversea; but, with full realization of the relationship between epidemic and epizootic plague, and with the application of proper measures, it would be expected that the number of vessels in which epizootic plague had been permitted to progress to a stage at which human infection became probable would be small, and would be, in any event, considerably less than the number . in which epizootic plague without epidemic plague had been detected.

Tt would appear, from the evidence available in this series, that human cases do not occur until rodent plague has become well established, and, it may even be said, has become extensive in distribution, which presupposes a considerable rat population.

Administratively, the significance of this fact is obvious. If vessels are kept free from rats they will not carry plague. If rat destruction is persistent and systematic, and is combined with routine examination of rats killed on shipboard, the earliest occurrence of rodent plague will be noted, and in this way the occurrence of human cases on shipboard will, except in respect of infection ashore, be anticipated and largely prevented.

From the point of view of the spread of plague within the Commonwealth, it is important that during the ten years in -which plague was present in Australia, only fourteen vessels were recorded on which plague either definitely or possibly of Australian origin occurred.

Three of these are epidemiologically of little importance, the presence aboard of shore-infected persons being, as it were, incidental, and of no significance in relation to the distribution of infection.

So far as is now known, then, eleven vessels were infected with plague in Australia, and became potential distributers of infection during a period of eleven years, during ten of which plague was present in two States, and during seven of which plague was present in three States.

In the earliest days of 1900, when plague first appeared in Australia, it is obvious from the records that the demands upon the various State Departments of Health3 were so great, and the realization of the part played by rats in the spread of plague as yet so incomplete, that it is probable there were some, if not many, instances of infected vessels which not only escaped detection by reason of the non-occurrence of human cases, but which actually carried the infection and were responsible for the occurrence of new foci of epizootic and epidemic plague, Of such there is, however, no record.

CHAPTER XVII —THE RELATIONSHIP BETWEEN EPIZOOTIC

AND EPIDEMIC PLAGUE.

Time Relationship.

The appearance, progress, and disappearance of human plague in a community has been shown to correspond closely with the same stages in the course of rat-plague over the area on which that community lives. The following tables are extracted from the official reports, and since the monthly distribution of human and rodent plague is not calculated to show with sufficient clearness the fluctuations which occur in the intensity of either over shorter periods, those tables of weekly incidence which are available from the official reports are also shown.

Table 32.

Human and Rodent Plague, Metropolitan Area of Brisbane—by Months

1900-1910.

G

__

C

<V

>>

CT

Eh

-t-j

>

3

O

1

Pi

ë

¿i

1-3

<

ET

GO

G

O

O

O

1900 Human . .

3

il

8

15

4

5

4

4

2

56

Rodent ..

. ,

5

3

15

21

24

15

7

90

1901 Human . .

1

7

7

12

3

3

1

1

1

36

Rodent . .

16

23

32

20

8

1

1

101

1902 Human . .

1

13

21

28

18

1

82

Rodent . .

3

6

7

53

16

12

8

1

106

1903 Human .

5

4

6

4

2

21

Rodent ..

1

8

30

20

15

6

4

84

1904 Human . .

5

7

11

1

5

1

30

Rodent . .

21

3

25

25

89

150

38

17

4

6

2

380

1905 Human . .

4

16

2

1

4

1

28

Rodent . .

5

59

48

3

7

5

1

1

129

1906 Human . .

2

2

2

2

2

1

11

Rodent . .

1

6

6

3

5

6

2

8

1

10

48

1907 Human . .

21

3

3

4

4

1

3

1

40

Rodent ..

4

6

1

5

3

3

4

6

5

2

5

1

45

1908 Human . .

4

2

3

1

2

1

1

14

Rodent . .

21

1

17

11

14

2

5

71

1909 Human ..

Rodent . .

1910 Human . .

..

Rodent .

Table 33.

Hum^n and Rodent Plague, Sydney—by Months, 1900-1910.

January.

Â

a;

March.

April.

!

ÿ '

i ne.

Sr

P

O

GO

S-h

d>

G

-G

G

O

Ta

ci

C

i o a

1900 Human

1

3

51

107

93

41

6

i

303

Rodent ..

9

2

6

5

1

23

1901 Human ..

1

1

2

Rodent . .

4

4

1902 Human

6

26

57

20

22

6

137

Rodent ..

5

25

6

37

23

4

1

101

1903 Human . .

1

1

2

Rodent . .

27

97

23

14

161

1904 Human . .

1

4

3

1

1

2

12

Rodent . .

4

32

35

89

50

6

20

5

1

1

243

1905 Human . .

2

9

5

1

17

Rodent

7

10

34

74

8

1

8

4

2

9

1

158

1906 Human

7

1

7

3

1

1

20

Rodent

1

15

29

21

2

12

24

23

40

3

1

3

174

1907 Human

14

14

10

5

2

2

47

Rodent ..

11

54

25

29

17

33

13

16

19

2

219

1908 Human Rodent

^Not availabl

e

1909 Human . .

11

9

1 4

..

. .

24

Rodent . .

3

10

78

63

20

4

178

1910 Human ..

Rodent

5

1 ..

5

Table 34.

Human and Rodent Plague, Metropolitan Area of Brisbane—by Weeks, 1900-1907

(From Report of Plague in Queensland, 1900—1907, page 26.)

Week-.

Year

-

1

o

O

4

6

8

9

10

11

12

13

14

.)

16

i

1S

19

20

21

23

24

25

26

07 — <

28

29

30

31

»

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

Total.

1900

Human

..

m .

, ,

1

o

2

1

i

9

1

• •

3

»>

1

H

5

1

2

1

5

o

5

4

6

6

i)

3

1

5

1

8

5

2

4

3

i

3

i

i

4

5

i

9

• •

9

1

1

• •

56

90

1901

Rodent

Human

Rodent

• •

i

5

O

*> * "

i

o

3

1

9

10

1

9

i

1

1

2

6

î

5

1

8

;)

5

3

4

3 1

4 1

3

3

6

1

1

8

io

*>

10

9

7

•3

9

1

4

0

1

9

5

1

o

* •

• •

• •

i

l

■ •

i

1

36

101

82

1902

Human

Rodent

• •

• •

1

i

l

i

1

3

1

2

4

1

*>

»>

5

il

1

1

\

3

1

1

16

0

26

1

6

7

5

1

4

11

i

H

i

5

5

3

4 1

1

i)

.)

1

4

4

O

o

O

3

• •

i

• •

• •

• •

• •

106

21

1903

Human

Rodent

i

1

1

4

1

1

«)

i

i

3

1

i

1

i

4

1

g

5

*)

6

1

96

O

4

1

41

1

1

9

i)

o

i

i

2

1

• •

• •

2

2

84

30

1904

Human

Rodent

i

3

if>

sy

1

3

1

i

3

1

4

O

4

13

1

o

«J

$

o

1

5

16

17

14

o

9

24

s

21

24

6

3

4

12

i

o

1

3

2

• •

• •

i

• •

2

2

380

28

1 905

Human

i

1

1

4

4

i

6

1

• •

• •

l

ï

1

‘i

•i

•i

1

i

1

i

129

Rodent

O

i)

1

• .

9

12

13

17

24

23

3

1

i

1

i

. .

..

1

i

5

11

1906

Human

, .

. •

• •

. .

i

3

1

• •

1

1

1

3

2

• •

r

1

1

\ i

5

i °

i

11

. ,

, ,

1

'..

' • •

• •

' 6

48

1907

Rodent

Human

Rodent

i

i

i

12

5

i

0

1

1

3

4

0

1

I

• •

1

1

1

3

1

O

1

i

5

Table

ended

at

30th

June,

1907

/

i

36

‘>2

'

1

1

Table 35.

Human and Rodent Plague, Sydney—by Weeks, 1903-1907. (From New South Wales Plague Report, 1907, page 45.)

Weeks.

i

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

(32

33

34

35

36

37

38

39

40

41

42

U

44

45

46

47

48

49

50

51

52

Total.

2

26

1

5

1

9

1

17

1

«

i

1

2

80

1

i 3

1

2

15

6

i

1

9

5

• •

• •

2

• •

• •

• •

• .

• .

■ •

• •

• ■

• •

■ •

• •

• •

• ■

• •

2

161

12

1

1

3

1

1

1

3

14

14

15

52

11

4

1

3

24

9

bad

1

• •

3

1

6

6

2

6

1

3

• •

- ■

1

1

243

17

1

# ,

r

. .

A

1

2

2

2

1

2

1

1

2

J

2

2

4

6

2

8

1

1

9

1

2

2

4

1

141

• •

2

5

4

1

3

2

8

10

3

7

4

7

9

8

13

34

1

3

1

1

4

1

6

1

O

1

1

y

1

1

20 1 71

1

i

9

5

10

4

3

2

10

17

3

1

1

3

2

• •

• •

4

2

6

7

5

6

6

3

25

i

O

Z

• •

L

2

47

i

i

6

5

2

7

3

28

6

12

6

11

2

3

3

7

2

4

3

5

2

9

4

2

1

3

9

9

6

4

1

7

3

8

11

10

4

7

2

• •

2

2

z

Z

12

11

ü

o

i

• •

i

• •

i

219


1903 Human Rodent 1 904 Humai» Rodent

1905    Human

Rodent

1906    Human Rodent

1907    Human Rodent

The information available is complete and reliable only for the two States—Queensland and Yew South Wales.

New South Wales.—Thompson, in his Plague Report for 1900, states:—“The above is the recorded evidence that rats over a considerable area of Sydney, which was the area on ’which cases of plague in man occurred, suffered from an epizootic; and that this epizootic (which began before plague in man occurred, and ceased, as far as can be learnt, about the same time as the epidemic ceased) was plague.” Again in 1906 (Address on Epidemiology of Plague, Congress American Medical Association) he said:—“The result of continuous examination of our rats has been to show us that rat plague always coincides in place with plague in man, and in time always precedes it; but the presence of plague rats was not always attended by plague in man. Out of many things which have been asserted of plague as the result of incomplete observation, occurrence of an interval between attack of the rat and attack of man stands out as a reality. We have seen it constantly; but we have also seen that it need not be long, as is generally asserted, but may be quite short. The occurrence of a definite interval is well exemplified by the following observations. We have good reason for believing that our rats were dying of plague on the first occasion during the first week of January, 1900, and that they had probably become infected some time before; but the first case was not attacked till 19th January, the second not until 17th February; and the disease did not become 'widespread till two or three weeks later still. In the second outbreak, immediately after the first case had been notified, we ascertained that the infection was already present at three or four separate points; namely at the produce store at which the patient had been employed, at a wharf where produce was habitually handled, and soon afterwards at another produce store, and at a stable a few hundred yards from it, all the latter having stood a little way inland of the wharf, and all having probably been infected 'per saHum from it. Yet there was an interval of 34 days between that first case and the second, and of 35 days between the second and the third. In 1903 the epizootic was recognized on 12th May; but the first of the only two cases which followed was not attacked till 17th June. On the fourth occasion the epizootic began 29th February at a certain produce store; the first person was attacked 9th March at that store, whence he had removed dead rats as late as 3rd March, and where others were afterwards found and plague in them identified; but the second case did not follow until 32 days later. An interval was observed on every occasion, both in districts and in houses.

Of this interval many mysterious thing's have been alleged; but I believe it is now hardly necessary to point out that the first step towards explanation of it lies in recognition of the simple requirement that time must elapse before the rats, which are usually first infected at such uninhabited places as wharfs, <fcc., can sufficiently penetrate to the dwellings of man. But another condition contributes to lengthen it, which cannot be so easily explained. An interval is always observed even between the invasion of individual

houses and the occurrence of cases in them. Now, the difficulty of identifying plague in rats has already been mentioned. It has arisen in this, that however soon after attack cases have been notified dead rats have been found, and usually they have been found jn an advanced stage of putridity. This is the common rule. Occasionally prompt notification has led to the discovery of fresh carcases; but always some of the rats found have died already. Plague cases do not occur till rats have died of plague in the house, or in its immediate neighbourhood; then, and not till then, may man be attacked.

With assistance of the first four outbreaks the seasonal incidence of plague can be fixed. The first or crude statement is the following:—The first epizootic began with January, and the last plaguerat was identified in August; the second began in November, and the last plague-rat was identified in July; the third began in May, and ended in August; the fourth began in March and ended at the beginning of December. But it requires some adjustment as to the beginning of the second and the end of the fourth outbreak. Although infection of the rats began in November, and evidence of it was found on four separate premises during the latter half of that month, no further evidence of it was got, notwithstanding continuous search, until the middle of January; in other words, nothing that could be called an epizootic then existed. The period of widespread plague in the rats did not set in until about the beginning of February. And as to the end of the fourth, although it actually fell in December, still the end of that which could be called an epizootic prevalence clearly fell in September; the plaguerats identified during the three latter months of that year numbered only five, two, and one respectively. So that the epizootic period may be fixed as falling between February and August, there or thereabouts. And the height of the epidemic period coincided nearly with the height of the epizootic; March, April, and May were the months in which the disease was most active in both forms—that is to say, in as far as we could estimate the smaller fluctuations of the latter.”

The conclusions arrived at by Ham from his experience in Queensland are similar, although more concisely expressed.

“That the epizootic (Rat Plague) and the epidemic (Human Plague) are commonly successive is a fact in harmony with the observation that when any animal succumbs or, indeed, is even moribund, from one cause or another the fleas that have been subsisting on it leave it and attach themselves to another animal host, should there be one that can afford them sustenance, and we may thus on occasion observe the co-existence of rats dead of plague, fleas, and human plague.

Rat mortality was invariably discovered in every indigenous centre of plague throughout tlis State, the rise in rat infection always preceding the manifestation of the cases in man. Epizootics occurred at periods when epidemics were prevalent, and both took place at certain seasons of the year which extended observation led us to anticipate. The association was observed year after year.

Sporadic cases in man during periods of quiescence were also attended by the presence of plague of sporadic occurrence in rats. The assumption that the epidemic was a consequence of the epizootic is further based on the fact that the dissemination of travelling plague cultures in the living bodies of rats was over areas which coincided with areas over which the epidemic was observed to extend. A reference to Table 34, and a survey of the graphs appended hereto, will show the weekly course of the epidemics and epizootics for the years 1900-1907 within the metropolitan area of Brisbane. The epidemic is marked by broken lines, the epizootic by continuous lines. The graphs correspond with Tables 34 and 35.

In connexion with the epizootic curves it may be explained that they only indicate approximately the proportional severity of the disease amongst rats, since the number actually found infected in the daily collection made for bacteriological examination must fall far short of the number naturally infected in the open, but, for obvious reasons, not obtainable. The rat curves, therefore, indicate the extent and result of the search, but cannot be considered as complete. It will be noticed for the years 1900, 1902, 1903, 1904, and 1906 that infected rats were discovered previous to the cases in human beings.

In 1901, 1905, and 1907, human cases apparently occurred early in these years, either before, or concurrently with, the mortality of rats; but on reference to the charts it will be seen that infected rats were found in the latter end of the year—<T7ovember and December immediately preceding those under discussion.

The conclusions deduced from a study of the charts are the following :—

1.    That a close association exists between plague in rats and

plague in man.

2.    That the epizootic invariably precedes the epidemic.

3.    That the epizootic runs concurrently with and outlasts the

epidemic.

4.    That an interval usually short elapses between the death

of rats and the attacks of human beings.

5.    That the curves of the epizootics bear a general resemblance

to the curves of the epidemics, the rise and fall in the

former being followed by a rise and fall in the latter.

6.    That both the epidemic and the epizootic exhibit a period

of incidence, stasis, and decline.

7.    That the incidence on both rats and man is heaviest in the

months of April, May, and June.

8. That from the middle of the year—end of June—to the

end of the year, there is a marked period of quiescence.

9.    That in a few years this period of freedom is broken by

sporadic cases both in man and rats.

10.    That both the epidemics and the epizootics have been of

comparatively modest dimensions. [Plague in Queensland, pp. 126-7.]

Fig. 6. The Course of Human and Rodent Plague in Sydney, 1903-1910. (Broken lines represent human cases ; full lines represent infected rodents).

Fig. 7. The course of Human and Rodent Plague in Brisbane 1900-1907. (Broken lines represent human cases ; full lines represent infected rodents).

Interval between Commencement of Epizootic and Epidemic.

While the general rule that any sustained rise in the epidemic curve is preceded by a similar rise in the epizootic curve, has been pointed out by both Thompson and Ham, neither of these writers has indicated at all definitely the time that elapsed before the one followed the other.

The following table shows approximately the periods in weeks which elapsed after the identification of plague in rats, before human cases were reported or vice versa, the position of the numerals in the columns indicating which began first.

Table 36.

Brisbane.

Sydney.

Rodents.

Human.

Rodents.

Human.

1900 ..

1

f

1901 .. ..

5

t

1902 ..

1

,.

t

1903 ..

1

4

1904 ..

3

1

1905 ..

*

6

1906 ..

5

3

1907 ..

*

*

1908 .. ..

t

..

1909 ..

t

• •

6

* Continued from previous year. t Information not available.

While no definite rule can be stated, it appears that the period is between one and six weeks, with a slight tendency towards the shorter period. This must be always subject to the efficiency of the search during interepidemic periods.

Epizootic Periodicity Amongst Different Rat Species.

This information is available for Sydney only, no published data in relation to other places in the Commonwealth being available.

The behaviour of the two species of rats in their relation to plague is shown in the following table and graph. In this connexion, Asburton Thompson states that:—

“Past records, and that for the present year, do not afford evidence that either species usually begins to suffer before the other. In 1903 infected specimens of M. decumanus were taken five weeks, and in 1905, eight weeks before any infected M. rattus was found; in 1904 and 1906, infected M. rattus was found five weeks and six weeks before infected M. decumanus; while in 1907 the first infected rats brought in were of both species. On six of the eleven premises on which both species were found in 1907, infected M. decumanus was first found, and the intervals after which infected M. rattus was first found were 5, 7, 9, 19, 27, 49, and 53 days. In the five houses where the contrary was the case, the intervals were 1, 21, 22, 184 and 187 days.    So that it does not

appear from the records that there is here any other than a casual connexion between plague in the one and in the other species.” (N.S.W., P.R., 1907, page 3.)

Table 37.—Species of Infected Rodents, Sydney—by Weeks 1903-1907 (From Report on Plague in New South \\ ales, 1907, page 45 (appendix D).)

Wee ks.

Year.


5 6


7 8 ;9 10


11


12


13


14


15 16


17


18 19 20 21


22 23 24


25126


97


28


29


30'31


32 33


34


35 36


37


38


39 40


41


42


43


44


45


46 47


48


49


50


51


52


1903


1904


1905


1906


M.

M.

m.

M.

M.

M.

M.

M.

M.

M.

M.

M.

M.

M.

M.


decumanus rattus .. musculus Total .. decumanus rattus musculus Total .. decumanus rattus musculus Total .. decumanus rattus . . musculus Total . . decumanus rattus .. musculus Total ..


1 3 10


i

20

1


10

1


14

3

17


26


26

30

3

1

34


17


10

11

4

1

2


14


14


66

13

1

80

1

10

4

15


10

13

1

36

15

52

1


i


11


2

1

12

15

1

3

4 1


2 1


24


1

1

2


28


1

12


4: 4 1


4 S


s!n


10


6 4 1

4 7


. 2


3

1

11


12


1

5

19

25

2

8

1

11


86

26

49

161

108

73

62

243

78

45 18

141

46 89 39

174

57

143

19

219


oo

00


Fig. 8. The Course of Rodent Plague in Sydney, 1903-1907. (Full lines represent infected

Effect of Period of Pregnancy on Numbers of Rodent Population.

Thompson iP.R., 1907, p. 31 discusses this interesting question as follows:—

In the following table there is shown the number of rats collected in twelve consecutive calendar months, the number of males and of females, and the number and percentage of pregnant females of each species:—

Table 38.

M. decumanus.

M. raltus.

Total.

M.

E.

Pr.

Per

cent.

Total.

M.

F.

Pr.

Per

cent.

1908—

January . .

1,058

726

332

48

14-4

927

514

413

68

16-4

February ..

1,369

961

408

55

13-4

952

582

370

65

16-4

March . .

763

426

337

39

11-5

748

413

335

51

15*2

April . .

609

365

244

25

10-2

613

338

275

35

12-7

May ..

852

533

319

16

5-3

1,161

693

468

60

12-8

1907—

June . .

584

381

203

18

8-8

1,053

743

310

48

15*4

July ..

374

215

159

16

10-0

490

265

225

34

15*1

August ..

494

279

215

34

15-8

702

437

265

54

20-3

September ..

422

252

170

27

15-8

639

373

266

53

19-9

October ..

447

273

174

37

21-2

984

612

372

91

24-4

November ..

587

382

205

41

20-0

741

504

237

35

14*7

December ..

550

345

205

27

13-1

477

282

195

26

13 3

“Broadly, the table shows that the percentage of pregnant rats fell from January to May, when the lowest percentage occurred, that it rose from May to October, when the highest percentage occurred, and that it had fallen again by December to a point a little below the level of the initial point in the preceding January. It may be said that both species bred during the whole year, and that there was slightly greater activity in this direction about September and October.”

Cleland (Bulletin of State Dept, of Public Health, W.A., Dec., 1908) reported a similar investigation, carried out on M. alexanclrinus caught at Fremantle and Perth. He summarizes the results of examinations extending over 2f years in the following table:—

Table 39.

Month.

Years.

Total rats examined.

Adult nonpregnant females.

Pregnant

females.

Percentage of pregnant females to total females.

April . .

1906, 1907, 1908

552

247

28

10*1

May . .

99

442

180

20

10*0

June . .

99

377

149

15

9*0

July

99

265

80

15

15*7

August ..

99

489

149

38

20*3

September

99

312

101

16

13*6

October ..

99

295

86

29

25*1

November..

99

684

214

59

21*2

December

9 9

321

88

42

32*3

January ..

1906, 1907

382

110

40

26*6

February ..

99

346

84

46

35*3

March

99

452

161

28

14*7

“ The above figures are, of course, rather small to generalise upon. The five months, October to February inclusive, however, seem to possess a distinctly higher percentage of pregnant rats than the other seven, and the young rats from these litters would reach maturity a little wdiile before plague is usually epidemic in man in the State.”

According to Ham (Qld., P.R., 1900-1907, p. 129) —“At Brisbane it has been ascertained that rats breed all the year round with but little variation in any particular month.”

The results may be conveniently recorded here of an interesting series of experiments in hybridization of rat species carried out in 1913 by Foreman-assistant G. C. Hughes, of the Commonwealth Quarantine Service. The deductions drawn by Mr. Hughes from his experiments were included in an unpublished report as follows:—

(1)    That the Mus rattus and Mus alexandrinus will breed freely either in captivity or at large. These experiments prove the former deduction, and the fact that the quarantine staff have captured nests of young containing both these varieties proves the latter.

(2)    That Mus decumanus will breed with neither the Mus rattus nor the Mus alexandrinus, and seemingly it is the doe of either species that is averse to the mating. In the case of the decumanus doe, as soon as either the rattus or alexandrinus buck starts making advances, the doe at once starts to worry and fight the buck. In the case of the decumanus buck making advances to either a rattus or alexandrinus doe, either of these does will repel his attentions, and the buck kills the doe in spite as a consequence. This deduction seemingly holds good even when the rats experimented with have been reared together from the time of being twTo or three weeks' only.

(3)    That until the age of puberty is reached the sexes of either the Mus decumanus, the Mus rattus, and the Mus alexandrinus will nest together comfortably.

Place Relationship.

There is no more important phase of the epidemiology of plague than the place-relation between epizootic and epidemic plague. Upon an accurate knowledge of the various aspects of this relationship alone is it possible to base accurately conceived administrative measures of plague control. It is probably correct to say that in all the literature of plague there is no record of a study of this epidemiological problem so detailed and so complete as that recorded by Ashburton Thompson in his seven reports upon plague, and in his communications to the American Medical Association Congress, the International Congress of Hygiene, and to the Journal of Hygiene.

The close analytical study of the behaviour of rat plague and of human plague in Thompson’s report on a Second Outbreak of Plague at Sydney, 1902, should he carefully and deliberately dissected by every student of the epidemiology of plague, as, even when so much is known of plague, there is much of primary importance on the practical side of the control of plague that is not mentioned in any complete way by other writers.

It is impossible in a brief review such as the present volume to do more than indicate the conclusions and principal considerations.

Thompson commences his discussion of this subject thus:—-“If man commonly received the infection from the rats—if epizootic plague were indeed the cause of epidemic plague at Sydney then coincidence between plague-rats and plague in man on the same premises should be demonstrable. But in the course of the review of the epidemic outbreak of 1900, we found that ¡we had not demonstrated it. Dr. Tidswell had, indeed, been enabled to identify but 23 plague-rats throughout the epidemic, and none of them were obtained from premises which had yielded cases of plague in man. Or, if findings of putrid carcases in which the nature of the disease, which, evidently, had been the cause of death, could not be rightly identified, be accepted as evidence of epizootic plague (as under all the circumstances it reasonably may), then dead rats in number were only observed on about 70 premises, although 221 premises were the adjudged places of infection for 255 cases. But there is no evidence that this discrepancy was a matter of fact; clearly it may have been apparent only, and may have resulted from the method of observation, which was certainly imperfect.”

During the outbreak of 1902, improved methods of observation were adopted, with the result that “whereas 113 cases have been adjudged to have been infected on 86 separate premises, and although plague rats were identified on 40 inhabited premises (be they dwellings or places of employment), plague rats and cases coincided but four times. Or, should that way of judging the facts be thought too rigid (as I have no doubt it is), then it can be stated that cases and the removal by the disinfecting staff of dead rats from the premises which were the adjudged places of their infection coincided only 47 times.

During 1903 only two cases of human plague occurred, in one "direct connexion with rats affected by disease was clear”; in the other “ no direct connexion with plague rats was established.”

During 1904 only twelve human plague cases occurred, and “close association writh plague rats wras shown to have existed in every one ■of this series of cases.” (1904, p. 25.)

After 1904 the position is described by Thompson—-

“During the outbreak of 1904 a special effort was made to ascertain whether close connexion between cases and plague rats could not be established in every instance, provided sufficient time

were devoted to the search. While only twelve cases occurred in connexion with nine places of infection, the presence of plague rats at each place was established. But although in the year referred to the number of cases and of places was extremely small, it had been found that the labour involved in the constant watchfulness of all concerned, which turned out to be necessary to success, and of long quasi-detective inquiries, were too great to be continued by a staff whose daily avocations were multifarious and exacting. During 1005, therefore, no special attempt was made to run the plague rat down in connexion with every case, although the more salient points wrere as carefully recorded as usual.” (P.B., 1905, p. 1.)

It may be assumed, therefore, that complete information was not collected in this particular point in 1905 and succeeding years. If Thompson’s conclusions may be assumed from the general bearing of his discussion of the subject, the deduction would be drawn that the direct connexion between human plague and rodent plague could be established in all cases if the conditions were such as to permit of complete “ inquiries into the circumstances of the patients at home, at work, and at leisure, into those of the businesses with which they were connected, into the state of the rats on premises occupied or frequented by them, into the state of neighbourhood of the premises as to rat infection and as to freedom from it, and the establishment of dates by documentary evidence whenever possible.”

Apart from the limitations of administrative practicability which prevent the intensive inquiries here postulated, there are other practical difficulties in connexion with rodent plague presented by natural conditions 'which are important enough to be indicated. Before dealing with these, however, it would be well to outline certain recorded facts, which, -while not modifying the general thesis of invariability of association between rodent and human plague, should be considered in association with it.

The limitation of association between rodent and human plague to individual premises is a very rigid procedure, and although it may be necessary to accuracy, in order to avoid the introduction of the hypothetical or the probable into the discussion, yet it does not exclude the consideration of other topographical distribution. For example, it was found, when a retrospective survey was made in 1904, that the relationship between rodent and human plague became more defined if larger areas were considered. A table showing the divisions of the City of Sydney, and the metropolitan municipalities, reveals “ that the feature which distinguished areas on -which cases occurred from others which yielded none -was the presence upon them of plague rats.” It is to be noted that the evidence for 1900 is defective, the necessary measures of rat search not having been carried out. As the conditions in this respect became improved, “ it appeared that plague rats

could be found always on areas which yielded indigenous cases.” On such areas plague rats were found in some occupied buildings which, nevertheless, yielded no case in man; sometimes, also, a vdiole area which at some parts carried plague rats, furnished no case in man. On the other hand, large and thickly-populated areas were seen in which the infection was closely limited. Thus in 1902, although Alexandria and Waterloo have a combined area of 1,830 acres, which carries 3,947 houses, the findings of plague rats were confined exactly to those neighbourhoods in which the cases of plague were found, or although Paddington has an area of 403 acres, which carries 4,386 houses, plague rats were found only on that very small part (of about 16 acres, carrying 163 houses) which has been named the Paddington area, where the cases which constituted that sub-epidemic were found. Again, Camperdown covers 435 acres, and carries 1,503 houses, but plague rats were identified only at premises in that street where the two indigenous cases of plague were met with. So also at Newtown, where the municipality covers 442 acres, and contains 4,521 houses, the only case of plague which happened there was found within half a dozen doors of the butcher’s where a local manifestation of the epizootic occurred, and at the same date.

There is good evidence then of close association in place between plague cases and plague rats.

In 1904 three cases occurred in metropolitan municipalities in remote and isolated areas; and “if it be asked what was the special circumstance which led to occurrence of the disease in these remote and isolated areas, it can be replied at once that it was the presence upon them of plague rats, since this alone distinguished them from very extensive tracts of town land which entirely surrounded them. The reason why these two distant places carried plague rats can also be assigned, for it is known that goods of particularly dangerous kinds were transported from infected premises to each of them. When the form in which the infection reached these distant localities is sought, doubt begins. Plague rats have not been detected in goods carried, or in course of being carried, to a distance by land, although, of course, rats have been commonly seen to be so carried. Actual transport of plague rats appear to me to be the best supposition.” (P.R., 1904, 23.)

CHAPTER XVIII. SOME DIFFICULTIES OF PLAGUE INVESTIGATION.

The difficulties encountered during an investigation to define the limits of association between rodent and human plague, are met in connexion with both human and rodent infections.

Difficulties in Tracing Sources of Human Infection.

The experience of 1902-3 illustrates these difficulties very clearly.

During that outbreak, there occurred 139 cases:—

“ From the total 139 cases, one, attacked on board the ship Eulomeiie, may be excepted (vide p. 72). Of the remaining 138, the place of infection was determined in 113; and that number of cases were adjudged to have received the infection on 86 different premises. Remain, therefore, 25 cases in which the available information did not suffice to indicate any particular place as probably having been that at which the infection was taken. Two of the 25 were Chinese; 4 of them were idlers or prostitutes; 3 were labourers out of work, who were taken ill while searching for employment; 3 others were boys under fifteen; and 3 were either rat-catchers or scavengers in employment of the local authority for the City of Sydney, whose occupation led them into special danger at many different places. There remain ten cases, therefore, in which it might be reasonably expected that the place of their infection would be discoverable. The history of each of them prior to attack was very carefully inquired into, and although nothing of apparent importance was elicited, the following data concerning some of them are worth mention. One was a druggist; one was a groom, who slept over a stable, and in the same building with his horses’ feed; another was a clergyman, actively occupied in district visiting; another habitually gathered mill-wastes for poultry feed at places on the Darling Harbour area; another was an unemployed man, apparently not an idler, but whose movements were obscure. Other three were housewives, one was a waitress at a restaurant, and one a barmaid. Evidently many of these persons ran, or were likely to run, into danger in the course of their occupation or idle wanderings, at a time when plague was epizootic and epidemic.’’—(E.R., 1902, p. 10.)

Difficulties in Establishing the Presence of Rodent Plague.

The City of Sydney provided conditions especially favorable for the epidemiological study of a disease like plague. “ The population numbered about 500,000. This population was not merely wholly white, of English extraction and speech, and fully civilized, but intelligent, instructed, and orderly, accustomed to direction, and amenable to it.” In view of these conditions, it might have been thought likely that vigorous and well-designed measures would have succeeded in detecting the presence of, and in eradicating all foci of, rodent plague wherever it existed. It has been sufficiently shown that, while the appearance of human plague was very frequently a sign-post pointing to the locality of a related epizootic focus, yet there existed a large number of epizootic loci, in which the infection was not communicated to any human. While, for administrative control of the epidemic, the declared presence of human plague indicated directions for active measures against infected premises, yet it was the repeated experience that human plague was not known in a freshly-invaded locality until epizootic plague had been existent for a considerable period of time.

Measures designed to secure immediate information of the presence of plague in epizootic form in any part of the metropolitan area were an essential feature of the plague campaign. For this purpose, a rat intelligence service was organized, and kept constantly active, during periods when neither human nor rat plague was being observed, as well as during periods of activity in either of these phases.

The first obvious difficulty is that, in a city of the size of Sydney, it is impossible in practice, whatever it may be in theory, to have a sufficient staff to continue anti-rodent operations over the whole area simultaneously throughout the year. A selection of areas was necessary, on the basis of either experience directing attention to them as specially liable to repeated rodent-plague manifestations, or the nature of the ground or the premises as being specially favorable for rat harbourage.

For the portion of the area not at any time being visited by this trained staff, the only measure found practical was the payment of a bounty for the carcase of each rat presented at a collecting station. The conditions under which these rats were ordinarily received were such that no reliable information could be obtained as to the place from which they had been taken. Consequently, it was decided at an early stage that laboratory examination of carcases received in this way was not justified.

The number of rats received, examined, and identified as plague-infected, is shown hereunder:—

Table 40.

New South Wales.—Rodents Collected and Examined.

Collected.

Examined.

Infected.

Percentage

Infected.

1900 ••

108,308

187

23

12-30

1901 (to 31.3.1902) .

47,522

1,967

40

203

1902 (from 1.4.1902)

54,282

40,669

65

0-16

1903 ■

88,829

33,169

161

0-48

1904

52,014

243

0-47

1905

91,119

31,895

141

0-44

1906 .. •

54,151

29,447

174

0-59

1907

90,375

31,621

219

0-69

1908

26,849

175

0-65

1909 .■ •■

26,744

17S

0-61

1910 ..

22,821

0

0-02

Table 41.

Brisbane.—Rodents Collected and Examined.

Collected.

Examined.

Infected.

Percentage

Infected.

1900 •

735

90

12 24

1901 •

1,851

101

5 46

1902 •

4.671

3,851

106

2 75

1903 •

24,050

14,153

84

0 59

1904 ■

52,566

24,642

380

1 54

1905 •

31,375

16,780

129

0 77

1906 . .

17,647

12,295

48

0 39

1907 .

14,808

10,379

22

0 21

1908

20,690

73

0 35

These figures represent a very extensive system of rat destruction and rat examination. The low percentage of infected rats identified as plague-infected is a striking feature of these tables.

This low percentage is explained by Thompson, as follows:—

“ But there are several considerations which show that such comparisons (i.e, between percentages), if they are made with a view to gauging the severity of an epizootic, are illusory. The most important of them is that the only methods practically available to rat-catchers tend to ensure capture of healthy rats for the most part. Those alone are taken in traps, as a rule, which are in good health, and which enter them in course of their active search for food; or, if infected, have not reached a stage of illness at which pathological signs have appeared. Hence, the percentage of identified plague-rats thus calculated must always be extremely small. An additional reason can be assigned for the low percentage which our accounts show; this attaches to the manner in which T

C. 5769—4

think it best to state the facts. A considerable number of carcases have been delivered at the laboratory in a state too putrid for useful bacteriological examination, but in which there was every reason to think plague has been the cause of death; and were these counted as plague-rats, the percentage would be increased. But I do not think the term “ plague-rat ” should be applied to any carcase in which the disease has not been identified; and I do not think that the term “ identified ” should be employed unless the presence of B. pestis has been bacteriologically demonstrated.— (New South Wales P.B , 1903, p. 13.)

In any endeavour to estimate the intensity of the epizootic on any premises, other difficulties are met:—

“ In the first place, the number of the horde which infested the building never could be ascertained; in the second, certainty that the plague-rats identified comprised all which had died of plague never could be reached. For, while in some instances very considerable numbers of carcases have been found, the rule has been to find but few, even on premises where it seemed certain the disease had had every opportunity of spreading.”—(New South Wales P.E., 1903, p. 15.)

The practical conclusion is that intelligence staffs can do no more than indicate the area over which an epizootic has extended. Even within this limitation, it is not possible to ensure with certainty that all plague-rats within this area are discovered.

“ Plague is commonly represented as spreading among the rats of a district with extreme rapidity, and as exterminating them almost. Contrary to reported experiences in many other countries, sick rats have not often been seen in the open at Sydney; the carcases picked up in streets and lanes were almost always putrid, and beyond reasonable doubt had been thrown out from premises on which they had died. The finding of plague-rats by the rat-catchers—particular premises being excepted, and reference made merely to buildings and their curtilages, which were examined in the ordinary course of the night’s work on infected areas—was not common. Then, again, we have no evidence of rapid spread over neighbourhoods.”—(New South Wales P.E., 1902, p. 216.)

“ As a rule, plague among rats in any district is so far from possessing a devastating character that its progress is slow, long drawn-out, and even insidious. The disease picks out individual rats, affects a minority of the horde at any one time, and exhibits its activity only in comparatively small, circumscribed areas which are successively attacked. On individual premises, I have occasionally found almost the whole colony dead; but this has been exceptional, and even there the rule has been that few plague-rats,

any many more healthy rats, have been collected during many consecutive weeks.”—(Thompson, International Congress Hygiene, see ISTew South Wales P.R., 1907, p. 63.)

“ Our general experience, as far as it has gone, shows that only a moderate, or even a small, proportion of adjacent premises may be infested with rats—apart from the question of plague— although from their structural state and use, nearly all of them appear equally likely to be so. Further, it appears that often the epizootic is largely confined to the rats inhabiting particular premises, and at any one time probably affects but a small proportion of the total rats in the district. Secondly, we have evidence of establishment of centres of infection by a mode of transportation from the local fons et origo which does not cause infection of the traversed interval, and of slow and irregular spread of the epizootic from them; while many adjacent buildings might at the same time harbour a plague-stricken horde. On the whole, this appears to be seldom the case.”—(h7ew South Wales P.R., 1902, p. 79.)

Quite apart from the difficulties in the way of detection of rodent plague, there are practical difficulties in the actual catching of rats on a large scale:—

“ During a term of eight months, the intelligence staff paid 17,656 visits to foreshores, wharfs, and stores; only 4,095 of these visits resulted in captures, and the number of rodents taken was only 10,579. The premises were entirely open to the men; but had the area examined been residential, it is clear the result would have been still less satisfactory, since admission at night would often have been refused to them. All buildings which seem to be likely to harbour rats are not infested with them. House-to-house examination of a group of blocks of squalid, but solidly constructed, buildings, which contained 387 houses, resulted in finding 57 infested with rats, or about 15 per cent, only; although all of

them,    from dilapidation, and a majority from the uses to which they were put, appeared equally exposed to infestation. These blocks,

then,    furnished an explanation of the erratic incidence of plague on houses—not in that these 57 were infected, but in that they alone were infested.”—(Thompson, Congress American Medical Association, see Xew South Wales P.R., 1905, p. 72.)

Where Plague-rats are Most Constantly Found.

u Analysis shows that plague-rats have been found most persistently at wharfs; then in warehouses and shops; then in stables; and then in more or less dilapidated cottages. One circumstance is common to all these kinds of places; either they are easily accessible to rats, or they are used in ways likely to attract rats. Such uses are the storage and distribution of food-stuifs. But there is

one use which is pre-eminently favorable to rat-infestation, this is the produce trade in hay, straw, chaff in bags, maize, and potatoes.”

(Thompson, Congress American Medical Association, see Hew South Wales P.R., 1905, p. 74.)

This coincides with the experience in Queensland:—

“ The incidence of plague, both in man and rats, was heaviest on particular localities where produce and grain were stored.”— (Plague, Queensland, p. 10.)

The Interval between Epizootics and the Bridge ” which Connects them.

Thompson, in discussing this, states that, while he does not deny the existence of plague in the rat in a chronic form, which causes but few deaths until something occurs to revive its virulence, he had yet failed to find any evidence pointing to it. (1906.) Yet, shortly afterwards, in his address to the International Congress on Hygiene, at Berlin (1907), he makes this statement:—

“ This evidence shows, I think, that epizootic plague may pursue a chronic course, and that its long continuance may not be attended at any stage by such a mortality as could not be easily overlooked.”

Prom this, it is probably permissible to deduce that Thompson's later opinion was that the bridgewas undetected rodent plague, except where the fresh appearance of the disease could with certainty be ascribed to a re-importation from some distant locality.

In connexion with this possibility of re-importation, Thompson, after discussing certain evidence, states that: “ It is reasonable to infer that coastal steamers have probably been an important means of maintaining plague in the Commonwealth from year to year, and special treatment of them is needed.”—(Hew South Wales P.P., 1907, p. 25.)

CHAPTER XIX.—RAT DESTRUCTION.

“ Rat destruction is a subject on which a great deal might be said. Extermination of the rat is impossible with any means thus far made available. Perhaps larger numbers have been destroyed during several years at Tokio than anywhere else, and yet it was hardly possible to recognize any impression made in the rat tribe as a whole. My own experience has been similar: but from time to time diminution in the numbers present in circumscribed districts has been produced by energetic poisoning and trapping. This has importance in relation to the limited areas over which the epizootic extends at any one time. But although occasions will arise from time to time on which effort may be directed to destruction of rats known to be present, as a rule infected neighbourhoods must be dealt with in a more general way, by scavenging and destruction of accumulations or places in which rats have been found, or probably may find harbourage, and especially by storing food and food-wastes so that rats cannot reach them. These operations should be guided, not by rats seen, or even traced, but by the conviction, otherwise acquired, that rats must be present, seen or not seen, wherever man has been infected, and can be driven out. Unless rat-staffs are firmly impressed with that belief, such operations will seldom be thoroughly successful.    *

“ Lastly, the difficulty in arresting rat-plague is in direct ratio to the bad construction of wharfs, quays, and the buildings upon or near them. The danger to man from plague is everywhere directly proportionate to the accessibility of the interior of buildings to rats, although it is quite absent outside them. When the difficulty of staying the infection by action directed to the rat is considered, and, above all, the impossibility of staying it within so short a period of time as shall effectually avoid the danger to man, I think it will be perceived that the rational method of defence lies in so improving the construction of buildings as greatly to impede the entrance of rats to them, and in so taking care of food that it shall not attract them.

“ In a broad view, then, all other measures must be considered as subsidiary to reconstruction of ill-built wharfs, stores, and warehouses, and to such repair and special fitting of inhabited houses as will keep rats outside them.”—(Thompson, International Congress on Hygiene, see New South Wales P.R., 1907, p. 67.)

CHAPTER XX.—SPECIES OF RATS WHICH ARE NATURALLY FOUND PLAGUE-INFECTED.

The following is Thompson’s recorded experience during the first six years of plague in Sydney:—

“A note on the species of Mm met with at Sydney, on their susceptibility to plague under natural conditions, and on the observed association of the different species with plague in man. The species are M. decumanus, M. rattus, together with its Alexandrine variety which it is unnecessary further to mention separately, and M. musculus. These comprise all which have become domesticated. Plague has been identified in all of them, and in such numbers as show, I think, that the proportions of each species enumerated in any year depended rather on local distribution than on any difference in susceptibility. In the first year to which I now refer, plague was identified in 86 I)., 26 If., and 49 M.; in the second, 106 D., 73 If., and 62 M.; in the third in 78 D., 45 R., and 18 M.; in the fourth in 46 I)., 89 R., and 39 M. I have found each of the two species of rats infected and associated with plague in man by itself, as well as the two together, on the same premises. Infected mice have never been found alone in that association, so that I have nothing which points to the mouse as an efficient cause of plague in man; on the other hand, I have not observations sufficiently extensive to show that it does not so act. In a short series of nine houses, infected M. musculus was once actually found alone in association with one case of plague, but rats had at the same time died in number on the premises, although none were secured in a state which admitted of identification of the infection; M. decumanus was associated alone in a second, M. musculus and M. decumanus together in a third, all three species together in a fourth and fifth, and ill. musculus with rattus in the remaining four. All the rats on the troopship Antillian (vide p. 71), on which was one case of plague on arrival, while another occurred in connexion with cleansing of the store-room, were decumanus. All those found on the other vessel, the Alsterschwann, were rattus in its Alexandrine variety; in that instance no one was infected, either among the crew or among the many persons engaged in unloading and in disinfecting her. In a rural district, 300 miles from Sydney, where twelve cases occurred in ten houses, all the rats (1,128) taken, whether in the houses or in farm buildings or on river banks, were decumanus with three exceptions; all the infected rats (101) were of that species, and there were two infected mice. At an important seaport 70 miles to the north of Sydney, where an outbreak consisting of fourteen cases occurred, plague was identified in 206 rodents out of 6,653 examined; 171 were decumanus, 13 were rattus, and there were 22 mice. The association of the infected species with plague in man at this place in the eleven cases which could be so examined was decumanus alone eight times, decumanus and m-usculus together twice, and decumanus, rattus, and musculus together once. The species found in connexion with two large warehouses at Sydney where eight cases occurred was rattus; all the patients recovered. That connected with six cases which occurred at a small hotel was also rattus, and two of these patients died. After having mentioned the caution that the following opinion does not result from complete knowledge, but only from what happened to be discovered, I may point out that the experience appears to indicate M. decumanus as rather the more susceptible, and practically rather the more dangerous. At all events, the suggestion recently made that in this relation M. rattus is the species to be feared, and that M. decumanus is, or, perhaps, may be, harmless, would fatally influence preventive operations at Sydney if it were adopted, and if it were possible to so conduct the destruction of rats as to spare the decumanus species on the ground that it would eventually destroy rattus. Doubtless there are variations in the susceptibility of the two species, and of each species in different countries, or even in different parts of the same country; but I incline to think that the proportions observed to be infected depend primarily on local distribution.”—(International Congress on Hygiene, Berlin, 1907, see Hew South Wales P.R., 1907, p. 64.)

Some other animals were proven to have received a natural infection of plague during the course of the outbreak. In New South Wales, four eats were infected, two at Sydney and one each at Woodford Island and Ballina. In 1902 an outbreak occurred at the Sydney Zoological Gardens in which the following animals died from an infection with b. pestis:—Four wallabies, one wallaroo, one pademelon, one tree kangaroo, one Indian antelope, three guinea-pigs.

The following table shows the number of rodents examined and found infected at Sydney from 1903-1920. The table—data from 1903-1920—is taken from the Eleventh Report of the Microbiological

Table 42.

Showing the Number of Rats Annually Examined from the First Appearance of Plague at Sydney in 1900

to 31st December, 1920.

V ear.

Period of Rat

Rats Examined.

Mice Examined.

Total.

Infected.

Percentage of infected to total examined.

Examina-

tion.

Decu-

Per

Ratlus.

Per

Mus-

Per

Rodents.

Decu-

Per

Rattvs,

Per

M us-

Per

Total.

D.

R.

M.

munus.

cent.

cent.

cuius.

cent.

marnisi

cent.

cent.

cuius.

cent.

t 1900-

-First pl<

a-gue out

break, IS

>th . lamia]

rv to 9 th

August.

t 1901-

2—Second plague outbreak, 12th November

1901, to 8th June, 1902

f Rats

1 Mice

1903

1st May to

8,695

• •

• •

• «

5,976

• •

14,671

t 111

/ 50

161

15 th Aug.

1094

1st Mar. to

12,169

27-76

8,225

18-76

23,428

53 48

43,«22

108

44 26

73

29 92

62

25-41

243

•76

1-16

0 26

3rd Dec.

1905

Year.

11,383

53 72

5,681

17-81

14,831

46 47

31,895

78

55 32

45

31-91

18

12-77

141

•79

•88

•13

1906

J)

9,275

31-49

8,694

29 52

11,478

38 97

29,447

46

26-44

89

51-15

39

22 41

174

•49

1 02

•34

1907

99

8,628

27-2

10,479

33 9

12,244

38-7

31,621

57

26 03

143

65 - 29

19

8-68

219

•66

1-3

•15

1908

99

7,622

28-39

9,207

34 29

10,020

37 32

26,849

82

46 86

78

44 57

15

8-57

175

1-075

•84

•14

1909

99

6,752

25-26

11,259

42-08

8,726

32-66

26,737

22

12-36

138

77 53

18

10 11

178

•32

1-22

2-06

1910

99

5,708

24 98

10,076

44 15

7,044

30 87

22,821

4

80 0

1

200

5

07

•009

1911

99

6,025

26-45

10,830

47 55

5,919

26 0

22,774

1912

9 9

6,510

37-82

7,922

46-18

2,722

16 0

17,154

1913*

99

5,020

47-29

5,477

51-59

118

1-1

10,615

1914

99

3,732

39-53

5,487

58 14

220

2 33

9,439

1915

99

3,592

37 13

5,946

61 -48

135

1 39

9,673

1916

99

2,807

35-33

4,967

62-53

167

2-1

7,943

1917

99

3,026

36-76

5,110

62-08

95

1 15

8,231

1918

99

2,601

33 43

5,109

65-67

69

88

7,779

1919

99

849

26-82

2,303

72-76

13

•41

3,165

1920

99

2,707

40-6

3,960

59-4

• •

• •

6,667

Total t

98,399

31-08

121,002

3S 21

97,229

30-71

316,632

397

34 • 98

567

49-96

171

15-06

1,135

64

0-88

•19

* Examination of rodents was suspended during the months of August, September, and October, owing to an outbreak of small-pox.

t No record was kept during this period of the actual number of rats examined, but they all belonged to one of two species—Mus decumunus and Mus rattvs. The infected specimens were all Mus decumanus. i inaccuracies in this Table are as in the original ; the percentages have been corrected.    P


L bor o ir r<ir|iorate<l ii the \\ - ual Report oí tie D ec    Ge e
o Public Health tor New South Wales, 1920, page 139):-

The following table gives the figures for Brisbane, so tar as they are available (Plague in Queensland, p. 131) The table has little value, as the total number of decumanus and of rattus examined is not known :—

T AliLK 13.

1904.

1905.

1906.

To 30th June,

1907.

Ex-

In-

Per

Ex-

In-

Per

Ex-

In-

Per

Ex-

Tn-

Per

ami i led.

fected.

cent.

amined.

fected.

cent.

amined.

fected.

cent.

amined.

fected.

cent.

Mus dtca-~\

r 309

1.551

87

0-65

16

0-14

13

0-14

man us 1

19,089

<

f

13,283

<

}

10,847

9,254

Mus rat- [

t 63

0-32 J

41

0-24

32

0-29

9

0-09

tus J

Mas mus-

4,903

3

0-06

3,497

1

0-03

1,343

. ,

1,125

ruins

CHAPTER XXI—SPECIES OF FLEAS CONCERNED IN PLAGUE TRANSMISSION.

In Thompson’s series of reports, this question is not very fully discussed, although early in the outbreak he accepted, on epidemiological grounds, the role of the flea in transmission, and his comments in this connexion show that he closely followed the confirmatory work of investigators in other countries. In the reports for 1900 (page 57) and for 1902 (page 71), Tidswell reports the results of flea investigations, and in a report on “ The Ectoparasites of the Rat ” in this latter report (1902) he gives the following table of species of fleas identified from various localities:—■

Table 44.

NUMBERS AND SPECIES OF ElEAS OBTAINED FROM DIFFERENT PARTS OF

Australia.*

Locality.

No. of Specimens.

Ty ¡.hlopsylla musculi.

Pulex

fasciatus.

Pulex serra Peeps.

Pulex

pallidus.

Brisbane . .

103

18

6

79

Perth . . . . . .

6

o

Newcastle .. . .

34

24

3

t

Sydney . . . . ..

100

8

10

l

81

New Zealand . .

50

3

53

The reports of the Hew South Wales Bureau of Microbiology give complete records of flea censuses by months from 1909 onwards. These are shown on page 109 seqq.).

Ham collected in 1907 (Plague in Queensland, p. 147) some information as to species of fleas in Australia.

“ The species of fleas that have been met with on rats and mice associated with man in Australia: Pulex irritans, Pulex cheopis, Ctenocephalus canis, Ceratophyllus fasciatus, Ctenopsylla mus-culi. Their relative frequency of occurrence, in connexion with the rodents named, in the principal cities in the different States is shown in the following table:—

Table 45.

Distribution of Rat-flea Species in Australia.

Queensland

Rockhampton

Townsville

New South Wales (1902)    .

Sydney (1904)

Newcastle

Western Australia (Perth) . Western Australia (during epi demic period)

Western Australia (during non-epidemic period) Victoria

Tasmania    . .


Total Number of Fleas Examined.

Irritans.

Cheopis.

Canis.

Fasciatus.

Musculi.

1,609

0/

0

0 18

0/

/o

90-8

00 vp •—1

0/

JO

0-37

K>o?

00

40

100

10

100

100

81

1

10

8

134

69

9

23

34

20-5

3

70

66

50

1-5

48-5

36

78

22

23

17

82-6

80 or 90

Only one was P. cheopis—all others were C. musculi or C. cams


290


0-3


1-4


Common

rat

flea


It is important tliat Ham’s original report should be consulted in connexion with this table, both for the sources of his information and for his annotations. Ham commented as follows (p. 148) :—

iC From the foregoing tables it may be concluded that—

(1)    In Queensland, in Hew South Wales, and Western

Australia the rat-flea that preponderates is Pul ex cheopis.

(2)    On the other hand, in Victoria and Tasmania it is

least prevalent.

“ This varying numerical representation bears no relation to the kind of rat most prevalent, for in Tasmania and Western Australia—where, in both alike, the commoner rodent is Mus rattus—we have the rat-fleas that preponderate different ones.

“ It is unnecessary to point out that the distribution of Pulex cheopis, both in time and place, has its strange counterpart in that of epidemic and, perhaps, also epizootic plague.”

In 1908-9 Dr. T. Bortliwick carried out a limited investigation into the flea parasites of rats in Adelaide, and his findings were reported in a note in the Australasian Medical Gazette for 20th May, 1910. A total of 80 rats were examined from Adelaide, Port Adelaide, and Port Victor, mostly in the latter half of 1908. The rats were—70 M. decvr manus, 6 M. rattus, and 4 II. chryogaster. Of the 418 fleas obtained, the species were identified as follows:

C. fasciatus, 137 on 27 hosts;

C. musculi, 203 on 23 hosts;

L. cheopis, 67 on 20 hosts;

C. londiniensis, 7 on 4 hosts;

E. myrmecobii, 4 on 2 hosts.

CHAPTER XXII-INFLUENCE OF SEASON ON THE OCCURRENCE OF PLAGUE.

Ham deals, in definite terms, with this aspect as follows (Plague in Queensland, p. 43 ) :—•

“ The most striking factor in tlie history of plague in Brisbane is the cyclical character of its annual increase and decrease. The development and decline of the eight epidemics of plague in Brisbane during the successive years 1900-1907 are shown in the chart attached.

“ A consideration of the chart as a continuous record will show the epidemic curve to be in fairly close agreement with that of the epizootic curve. Both reach their maxima in the autumn months of April or iviay, are lowest in the winter months of June or July, and are normal, or absent altogether, during the spring and early summer months of the latter half of the year.

“ The cases in human beings are observed to begin during the hot and moist or “ muggy ” season of the year—the end of January and the month of February—reach their limit about May, and notably decline at the beginning of June, when the colder weather with dry westerly winds sets in.

“ It has been suggested by some observers that the seasonal variation of plague may be due to seasonal increase of plague amongst rats. A more feasible explanation of this variation may, perhaps, be found in the prevalence and activity of insect life, notably fleas, and the development of the egg, larva, and pupa of fleas under certain environmental conditions. It was noticed that during an epidemic of plague little difficulty was experienced in collecting the fleas from off the rats, hut towards the end of the epizootic the number of fleas on rats was small.”

Thompson dealt briefly, but concisely, with the conditions so far as Sydney was concerned—

The greatest prevalence of epidemic plague has occurred with us during March, April, and May. That is the season when most people suffer, and when rats most suffer. It is also the season of fleas.”—(Congress of American Medical Association, 1906.)

Appended is a series of tables showing the seasonal prevalence of fleas in Sydney according to species. Interruptions in the records of examinations in 1913 and 1919 were the direct result of pressure of work in connexion with the outbreaks of small-pox and of influenza during these years.

These tables are taken from the Annual Reports of the Bureau of Microbiology.

In Western Australia, as will be seen by reference to the previous chapters, the months of greatest plague incidence were February and March.

Table 46.

Human and Rodent Plague and Prevalence of Flea Species, by Months, Sydney, 1909-1920.

(From Annual Reports of Bureau of Microbiology, New South TVales.)

Ye til.

Human

Rodents

Number

Plague-

Infected.

(Laemopsylla) Xenopsylla cheopis.

Ctenopsylla

musculi.

CeratophyUus

fasciatus.

Cases.

Examined.

Gross.

Per

1,000

Rats.

Gross.

Per

1,000

Rats.

Gross.

Per

1,000

Rats.

1909—

January . .

1,865

3

108

57

81

43

52

26

February ..

2,355

10

120

50

60

34

11

4

March . .

11

2,930

78

331

112

77

26

35

11

April .

9

3,225

63

314

97

42

13

8

2

May . .

4

3,428

20

108

31

38

11

5

1

June . .

1,918

4

55

28

25

13

4

2

July

1,915

42

21

20

10

10

5

August . .

1,522

9

5

16

10

1

63

September

1,518

76

50

62

40

5

3

October

1,835

16

8

50

27

47

20

November

1,713

3

2

15

8

6

3

December

2,400

9

3

28

11

26

]<*

1910—

January . .

1,825

14

8

41

22

36

20

February . .

1,798

88

49

34

19

19

11

March . .

1,717

80

47

33

19

23

13

April . .

2,130

5

139

65

48

23

11

5

May . .

2,118

43

20

37

17

5

2

June . .

1,750

54

31

56

32

13

8

July

1,923

44

23

57

30

24

12

August . .

2,043

67

33

46

23

28

14

September

1,949

121

68

88

45

48

25

October

1,849

20

11

87

47

33

18

November

2,179

11

5

6

3

9

4

December

1,540

20

13

8

5

17

11

1911—

January .

1,711

97

57

46

27

53

31

February .

1,745

316

181

106

61

20

11

March .

1,726

191

111

59

34

12

7

April .

2,522

103

41

37

15

13

5

May .

1.941

47

24

57

29

11

6

June .

1,612

17

10

28

17

3

2

July

2,235

122

54

121

54

16

. 7

August .

1,789

55

31

124

69

38

21

September

2,291

27

12

205

89

66

29

October

1,561

26

17

97

62

54

34

November

1,804

43

24

106

59

38

21

December

1,837

61

33

79

43

51

28

1912—

January . .

1,606

44

27

23

14

24

14

February ..

1,404

129

91

14

9

7

4

March . .

1,701

128

75

25

14

18

10

April . .

1,264

66

52

45

35

9

7

May . .

1,602

59

36

12

7

2

1

June . .

1,603

62

38

32

19

11

6

July

1,213

42

34

15

12

17

14

August . .

1,434

30

20

67

46

14

9

September .

1,045

14

13

40

38

9

8

October .. . .

1,326

17

12

75

56

31

23

November . .

1,781 ..

11

6

34

19

29

16

December .

1,175 ..

39

33

60

52

48

40

110

Table 46—continued.

Year

Human

Cases.

ltodents

Examined.

Number

Plague-

Infected.

(Laemopsylla) Xenopsylla cheopis.

Ctenopsylla

musculi.

Ceratophyllus

fasciatus.

Gross.

Per

1,000

Bats.

Gross.

Per

1,000

Bats.

Gross.

Per

1,000

Bats.

1913—

January . .

. .

1,436

30

21

7

5

11

8

February . .

. #

1,781

77

43

24

13

5

3

March . .

933

29

31

3

3

April . .

1,469

11

7

4

3

May

1,846

28

15

17

9

2

3

June ..

1,171

62

53

27

24

4

1

July

. .

1

August . .

>■ Examination interrupted by small-pox outbreak. No

September

complete returns available from end of June

October . .

November

929

December

776

1914—

J anuary . .

824

25

30

5

6

2

2

February . .

836

March . .

661

29

43

2

3

April ..

726

33

45

3

4

May . .

726

June . .

708

2

2

July

753

12

15

2

2

1

i

August ..

885

21

23

44

49

6

6

September

953

14

14

48

50

27

28

October

923

55

59

234

253

37

40

November

728

8

10

24

32

14

19

December

716

36

50

7

97

7

97

1915—

January ..

907

88

97

4

4

i

7

February

898

8

8

1

1

1

1

March . .

949

77

81

7

7

5

5

April ..

729

14

19

26

35

2

2

Mav ..

917

1

1

6

6

June ..

649

18

27

8

12

July

744

13

17

33

44

3

4

August . .

768

15

19

27

35

3

3

September

661

5

7

27

40

12

18

October . .

907

5

5

6

6

23

25

November

835

5

5

. ,

6

7

December

709

3

4

11

15

10

14

1916—

January . .

720

73

101

11

15

4

5

February . .

856

120

140

12

14

30

35

March ..

712

43

60

17

23

13

18

April . .

600

9

15

10

16

9

15

Mav . .

835

16

19

13

15

June . .

625

3

4

July . .

744

26

34

10

13

8

10

August . .

748

. .

• .

September

593

7

11

11

18

6

10

October . .

515

November

498

.. 3

6

19

38

6

16

December

1

497

5

10

. .

Ill

Human and Rodent Plague, etc.—continued.

Year.

Human

Cases.

Rodents

Examined.

Number

Plague-

Infected.

(Laemopsylla)

Xenopsylla

cheopis.

Ctenopsylla

musculi.

Ceratophyllus

asciatus.

Gross.

Per

1,000

Rats.

Gross.

Per

1,000

Rats.

Gross.

Per

1,000

Rats.

1917—

January . .

508

February ..

552

104

188

13

23

March .

671

38

56

3

4

5

7

April . .

699

2

2

4

5

May ..

879

5

5

4

4

6

5

June ..

675

• •

July . .

721

• •

. •

August ..

837

September

645

22

34

10

15

1

1

October

788

21

26

3

3

16

21

November

720 ..

4

5

23

31

10

13

December

536

1

1

* *

1918—

January ..

582

12

20

5

8

14

24

February ..

721

7

9

6

8

1

1

March . .

. . 726

5

6

1

1

3

4

April ..

760

20

26

6

7

2

2

May ..

706

1

1

3

4

June ..

546

2

3

5

9

July ..

698

2

2

1

1

10

14

August ..

710

8

11

18

25

3

4

September

699

4

5

12

17

2

2

October

586

6

10

2

3

6

10

November

444

• .

• .

4

9

6

13

December

601

* •

• *

* *

* *

* *

1919—

January ..

500

10

..

February . .

165

• •

..

March ..

172

• •

. .

. .

April ..

28

..

« .

. .

May . .

323

32

4

14

June ..

284

22

3

16 '

July

288

August ..

340

September

316

^Examination interrupted by influenza

October .

223

epidemic.

November

208

December

318

J

1920—

January . .

480

.

* »

February . .

614

89

144

14

22

12

19

March . .

650

34

52

19

29

12

18

April . .

495

32

64

18

36

4

8

May ..

550

37

67

22

40

13

22

June ..

498

33

66

15

30

5

10

July . .

574

7

12

6

10

5

8

August . .

541

9

16

8

14

8

14

September

492

5

10

26

52

21

42

October

608 ..

6

9

16

26

39

64

. November

597 ..

6

10

23

38

23

38

December

568 ..

44

79

35

61

27

47

Table 46—continued.

Year.

Human

Rodents

Number

Plague-

(Laemopsylla) XenopsyUa cheopis.

Ctenopsylla

musculi.

Cerato phylli's mciatvs.

Cases.

Examined.

Infected.

Gross.

Per

1,000

Rats.

Gross.

Per

1,000

Rats.

Gross.

Per

1,000

Rats.

1921— January . .

433

27

62

52

120

23

53

February ..

477

40

84

15

31

29

61

March ..

443

17

38

3

/

April . .

593

40

67

41

69

15

22

May . .

773

52

67

85

no

1

1

June ..

500

34

68

51

102

19

38

July . .

464

49

106

83

179

17

37

August .

519

26

50

12

23

19

37

September

Plague outbreak. See

page 196 for continuation of

record.

PART II—THE INTER-EPIDEMIC PERIOD, 1910-1920

CHAPTER XXIIL—MEASURES ADOPTED AGAINST THE INTRODUCTION OF PLAGUE, 1910-1920.

The first epidemic of plague in Australia covers a period of nearly ten years, commencing with the discovery of infection in Sydney in January, 1900, and terminating with the two cases reported in Mackav, Queensland, in June, 1909. In 1909, there were cases also in Sydney, Brisbane, and Adelaide.

Xo case of plague in man appeared again in Australia until 20rd August, 1921.

Development of the Federal Quarantine System.

The intervening years saw in Australia the abolition of the State systems of quarantine, the Commonwealth undertaking quarantine as a matter for which, by the Constitution, it was authorized to legislate. This was the consummation of the recommendations of the Australian Sanitary Conferences of Sydney, 1884 and 1896, convened when smallpox had become a question of quarantine importance to the Colonies, and also of the Intercolonial Plague Conference of 1900, which had taken the Vienna Convention of 1897 as a basis of discussion, but had recognized the importance of the rat as a factor in relation to plague more clearly than had the International Convention of 1897 (Tee Appendix A). The resolutions of these Australian Conferences had guided the quarantine legislation in the several States along more or less uniform lines of general policy, but in practice considerable overlapping and confusion had occurred prior to the advent of a federal form of control. The draft legislation for a Federal Quarantine Act was discussed in conference by the principal Health officers of the various States in 1904, and again in 1909, when various details of practical administration were laid down, the principles adopted not being divergent from the aims and objects of the International Sanitary Convention of Paris, to which the Commonwealth became a signatory in 1909. A quarantine service, a branch of the Department of Trade and Customs, but under the immediate control of a medical Director of Quarantine, was created to administer the provisions of the Quarantine Act, which came into force on 1st July, 1909. Quarantine regulations were proclaimed, prescribing the requirements and measures provided for in the Act.

In 1912, Dr. W. Perrin Xorris, the first Director of Quarantine, made an official tour of inspection abroad, during which he visited and inquiried into the quarantine organizations in the United. States of

America, Canada, England, Germany, France, Egypt, Aden, Colombo, Singapore, Japan, Honolulu, and Manila. His report, “ Quarantine in other countries and the quarantine requirements of Australia,” appropriately formed the first service publication issued by the Federal Quarantine Service. In later years, other publications were compiled for the information of quarantine officers, dealing with various phases of quarantine administration and practical procedure. In connexion with plague, there were issued a descriptive pamphlet of the species of rodents found in Australia, and a review of recent literature on the epidemiology of plague, with original observations of practical points on rodent control on vessels and on shore, with especial reference to Australian conditions. From 1916 onwards, a fortnightly bulletin was circulated, summarizing for quarantine officers the latest reports concerning quarantinable diseases in overseas countries, with especial reference to plague and small-pox.

rlhe Quarantine Act was amended in various particulars in 1912, 1915, and 1920, and the regulations corrected in accordance with recent developments in the practice and principles of disease control. Thus definite quarantine measures were provided against the introduction of plague, and were enforced at all ports by quarantine medical officers and a trained staff under the administrative control of a chief quarantine officer in each capital city, directly responsible to the Director of Quarantine. On 7th March, 1921, a Commonwealth Department of Health came into being, the quarantine service being incorporated as a division of marine hygiene, and carrying out, under the control of the Director-General of Health, the provisions of the Quarantine Act.

The operations of the quarantine service ensured a full medical inspection of all persons on every ship from oversea, whilst inquiries were initiated into the sanitary history of the voyage before pratique was granted. Included in the primary health report submitted by the master at the port of entry in Australia were the following questions: —

(a)    Is there now, or has there been during the voyage, any

unusual number of rats or mice on board ?

(b)    Have any dead or apparently sick rats or mice been found

on board during the voyage?

A question was also asked as to whether during the voyage any person had been affected with any illness attended with glandular swelling. In regard to vessels from plague-infected ports, quarantine officers were instructed to obtain specific information as to the measures taken to prevent infection during the vessel’s stay at those ports. Inquiry was made as to whether the vessel was berthed alongside a wharf or lay out in the stream; if the former, what steps were taken

to prevent the migration of rats to and from the vessel; if the latter, to and from the lighters; the nature of the cargo; whether the vessel was fumigated, and, if so, before or after the loading; whether any passengers were taken on hoard at the port; if so, whether inspected before embarkation; whether any passengers left the ship during its stay and visited the port; whether the passengers’ effects and cargo were disinfected before being placed on hoard. Instructions were given to the masters of vessels as to the requirements of the berthing regulations in Australian ports, and an inspection instituted for evidences of rodent infestation, both in cargo likely to show such infestation, or in Those special places in a vessel where these are likely to he found. As a routine, all second-hand clothing and all baggage of deck or steerage passengers from a proclaimed place was subjected to fumigation. The regulations in force very definitely provided for the measures which were to he adopted against the ingress to or egress from a vessel of rodents, and for the destruction of rodents which might exist on a vessel. These special measures were contained in Part IV. (Special Measures against Plague and Cholera) of the Quarantine Pegulations 61 to 66a:—

61. (1) The master or owner of any vessel in any port in Australia shall—    *    *

(a)    effectively obstruct by means of stout netting or other means

all openings or holes in the side of the vessel next to any wharf or lighter or other vessel, and shall keep them so obstructed while the vessel is alongside such wharf or lighter or other vessel;

(b)    affix and keep affixed an effective rat guard, disc, or screen

not less than 1 foot or more than 3 feet from the side of the vessel to every rope or hawser connecting the vessel with any wharf or lighter or other vessel;

(c)    when so ordered hv a quarantine officer, thoroughly

illuminate, from sunset to sunrise, with electric or other brilliant lights, the whole of the side of the vessel next to the wharf or to any vessel or lighter lying alongside;

(cl) remove at sunset, and keep removed until sunrise, the landing stages and all nets and gangways between the vessel and any wharf, except during such time as those landing stages, nets, or gangways are required for the discharge or loading of cargo, or for access of persons to and from the vessel, and are actually being used for such discharge, loading, or access; and

(e) take any other necessary and practicable measures to prevent the migration of rats to and from the vessel.

(2) JSTo rat guard, di3C, or screen shall be regarded as effective for the purpose of these Regulations unless it complies in all respects with the following requirements :—

(a)    it shall be circular in outline, formed in the shape of a cone,

and shall measure not less than 6 inches from base to apex, and not less than 24 inches directly across any diameter of its base rim to rim;

(b)    it shall be made of sheet metal of at least 26 gauge, without

any opening or perforator, except as hereafter specified;

(c)    it shall be so constructed that when fitted the apex of the

cone shall point away from the vessel and the rope or hawser shall pass through the apex of the cone and the centre of the base, and all openings in the disc, screen, or guards shall be effectively closed.

62. The master or owner of any vessel in any port in Australia shall—    '    1

(a) thoroughly empty, or flush out and empty, the bilges prior to berthing the vessel;

(h) keep all foodstuffs and food refuse in rat-proof and mouse-proof receptacles, rooms, or compartments;

(c)    prevent the discharge of any organic refuse, galley scraps,

and waste from the vessel on to the Avharfs or into the waters of the port;

(d)    maintain on board and use effective means for the destruc

tion of rats and mice; and

(e)    when so ordered by a quarantine officer, lay on the vessel

poison baits effective for rats and mice.

68. The master or owner of any vessel in any port in Australia shall, if so ordered by a quarantine officer—

(a)    submit any part or the whole of the vessel to sulphur fumi

gation as prescribed, or to some other approved method of fumigation, or to such trapping or poisoning operations for the destruction of rodents as are specified in the order. If so directed by the quarantine officer, the fumigation or trapping or poisoning operations for the destruction of rodents shall be carried out while the vessel is alongside a wharf or while the vessel is in stream, and either before or after the cargo has been discharged;

(b)    wash or spray thoroughly with the prescribed insecticidal

solution all portions of the vessel likely to harbor or to afford a shelter for fleas, lice, bugs, and other vermin;

(c)    empty and flush or disinfect and clean all lavatories, water

tanks, or any closed space on hoard the vessel:

Provided that in any case where there is reasonable cause to apprehend that the vessel may he endangered by the removal, of water ballast, the quarantine officer may cause any tank or other receptacle to he sealed; and thenceforward, so long as the vessel remains within the port, the master shall prevent the breaking or removal of the seal or the discharge or removal from the tank or receptacle of any part of the water ballast except with the written permission of the quarantine officer;

(d)    cause to he disinfected or fumigated any articles specified hv the quarantine officer;

(e)    remove and re-stow or re-arrange, in such a manner as to

prevent access or harbourage of rats or mice, any dunnage, rubbish, or deck cargo;

(/) remove, open up, or otherwise render thoroughly accessible to fumigation any linings, casings, partitions, lockers, and similar enclosed spaces above or below deck;

(q) protect effectively against the passage of rats or mice all openings, other than doors or hatches, which are liable to afford communication for rats from any hold or cargo space to any other part of the vessel; and

(h) protect effectively against the passage and harbourage of rats or mice any specified opening or place, whether below or above deck.

(13a. The master or owner of any vessel in any port in Australia shall, when the vessel is about to undergo overhaul or to be docked for repairs, or for any other purpose, give notice to that effect to the quarantine officer at least twenty-four hours before the beginning of any such overhaul or before the vessel is taken to the dock.

64. The master or owner of any vessel on arrival at any port in Australia from a place proclaimed infected with plague, or as a place from or through which plague may be carried, shall—

(a) submit the vessel to fumigation and other treatment as prescribed for the destruction of rats, mice, and other vermin:

Provided that the vessel may be exempted from fumigation if the master produce—

(i) a certificate showing that at the port of departure the vessel, while empty or after loading for the current voyage, was fumigated as prescribed; and

(ii) a certificate or certificates showing that at the port of departure (if a proclaimed place), and at every proclaimed place subsequently called at, effective measures were taken to prevent the migration of rats to the vessel. The measures adopted shall be specified in the certificate.

The certificate or certificates in each case shall be signed by the Port Health Officer or local quarantine officer if the proclaimed place is within the British Dominions, or be endorsed by the British Consul if the proclaimed place is a foreign port or country:

Provided further that in the absence of such certificates the vessel may, if no plague-infected rats or mice have been found on board, be exempted from fumigation at any port of call in Australia excepting the terminal port;

(b) if so ordered by a quarantine officer, discharge the cargo into lighters in stream.

65.    The following processes are prescribed:—

( n ) Por the destruction of rats and mice in closed spaces in vessels—thorough sulphur fumigation for at least eight hours with a gaseous mixture containing not less than three parts per centum of sulphur oxides. The fumigation shall, wherever practicable, be effected by passing .sulphur fumes under pressure into the closed space, the contained air being at the same time partially exhausted;

(b) for the destruction of insects and other vermin in vessels— sulphur fumigation as prescribed, or thorough application of an aqueous solution or emulsion of soft soap, cyllin, and kerosene, containing of each one part per centum. The application must he made by means of a mop or scrubbing brush or similar appliance, or by forcibly spraying the mixture into all places infested with or suspected of being infested with fleas, lice, bugs, or similar insects or vermin.

66.    Bor the purpose of these Regulations, “wharf” includes any pier, stage, landing place, jetty or similar structure, foreshore, or place at which a vessel may lie.

Control of Rodents on Vessels.

Bor practical routine purposes, quarantine regulation 64 in regard to the fumigation of vessels from infected oversea ports, was interpreted to ensure that every vessel from oversea was fumigated when empty at the terminal port called at in Australia. Sulphur-dioxide was used as a routine, a barge installed with a Clayton machine being available at Bremantle, and barges with the Ritchie modification of the Clayton

machine at Sydney and Brisbane. Otherwise, the tub method was adopted, and with intelligent supervision gave satisfactory results. Hydrocyanic gas and the Harker carbon-monoxide method were tried in an experimental way, and were used on occasion under special circumstances.

On coastwise vessels trading either between inter- or intra-state ports, fumigation was effected at least once every three months. During the stress of the war-time period it was found necessary to extend this period to six months, which is in accordance with the period specified in article 26 of the Paris Sanitary Convention.

Systematic trapping and poisoning were, in addition, carried out on both oversea and coastwise vessels, either at regular intervals or as occasion demanded.

The following table summarizes the fumigations of vessels carried out by the quarantine service in the more important ports of the Commonwealth from 1916 onwards:—

Table 47.

Ketitbx of Vessels Fumigated.

State.

Port.

1916.

1917.

1918.

1

1919.

1920.

To 30th September 1921,

Victoria

Melbourne

34G

248

310

283

268

215

Geelong

29

6

19

.New ¡South Wales . .

Sydney

714

628

712

710

743

669

Newcastle

137

/ 151

67

68

273

186

(Half-

year)

Queensland

Brisbane

102

80

99

67

120

102

Townsville

35

49

35

*

*

35

Cairns

22

12

10

*

*

4

Darwin

13

7

*

*

2

Thursday Island

8

85

87

*

*

60

Rockhampton

11

3

*

*

*

2

Mackay

1

*

*

*

*

*

South Australia

Adelaide . .

15

39

57

127

78

87

Port Pirie

27

24

17

43

26

17

Wallaroo

1

12

9

27

10

12

Port Lincoln ..

4

1

2

4

8

Port Victoria ..

6

3

2

Port Augusta

1

2

Western Australia . .

Fremantle . .

39

95

78

78

97

45 and

all

barges

Bunbury

13

7

5

31

47

43

Busselton

1

5

Albany

1

2

2

1

4

1

Geraldton

2

1

Broome

12

3

Tasmania

Hobart

4

36

49

33

19

25

Grand Total ..

1,480

1,508

! 1,548

1,499

1,699

1,539

* Complete figures for outports in Queensland are not available for the years 1919, 1920, and 1921.

Examination of rats trapped or killed by fumigation during the period under review failed to find any evidence of plague infection.

Control of Rodents on Shore.

The rat-proofing of premises ami rodent destruction and examination on shore (which included wharfs and water frontages) remained a province of the State Health Departments, and was either carried out by the Departments concerned, or delegated to the local authorities under the several State Health Acts. . In Sydney, both State and municipal rat-staffs operated and submitted rodents for examination to the State microbiological laboratory. In Queensland, rodent destruction and rat-proofing of premises passed from the State Health Department to the local authorities under the Rat and Mosquito Prevention and Destruction Regulations 1916. A rat gang continued, however, to be employed by the Slate Health Department to deal with Government property, shipping companies’ wharfs, and meat works in Brisbane.

The records of rat destruction and examination for the several States are not complete, excepting those for Sydney, which have already been shown on page 104. The following tables give the number of rodents examined in Queensland during the period under review, and the available records of species of rodents examined, from Brisbane, 1909-12, and from Townsville, 1912-15, at which latter date the northern office of the State Health Department was abolished.

Routine weekly statements of the results of rat examination were made by the Health Departments of the several States to the Commonwealth Quarantine Service. During this period no infected rodent wras reported in Australia. A mention should be made of the fact that on 7th April, 1914, the Health Department of Queensland reported that two smears of rat-spleens from Townsville showed bacilli “ suspicious of plague.” Inquiry showed no evidence of rat-plague epizootic in Townsville. Ultimately the Director of the Laboratory of Microbiology decided the microscopic appearance of the bacilli did not justify a diagnosis of plague.

Table 48.

Examination of Rodents! for Plague.—Queensland. (From Annual Reports of Commissioner of Public Health.)

Brisbane.

Townsville,

Cairns.

Maryborough.

Bundaberg.

Fiscal Year.

1st July to :50 th June.

Bats.

Mice.

Total.

In-

Bats.

Mice.

Total.

In-

Bats.

Mice.

Total.

In-

Bats.

Mice.

Total.

In-

Bats.

Mice.

Total.

Tn-

fected.

fected,

fecte d.

fected.

fected.

1909 1910

21,489

3,284

24,773

2,580

156

2,736

271

7

278

2,392

615

3,007

1,132

48

1,180

1910 1911

28,066

2,479

30,545

2,936

220

3,156

406

3

409

4,369

756

5,125

1,093

32

1,125

1911 1912

24,703

1,919

26,622

2,741

198

2,939

a

4,930

827

5,757

832

27

859

1912 1913

8,420

755

9,175

4,038

38

4,076

• •

4,034

771

4,805

703

93

796

1913 1914

9,165

653

9,818

# #

. .

2,913*

■ *

4,420

715

5,135

840

36

876

1914 1915

6,060

866

6,926

. .

2,223*

928*

. *

a «

2,050*

1915 1916

9,084

677

9,761

1,701*

754*

• •

*

544*

• *

m a

1,278*

1916- 1917

1,823

259

2,082

# a

a .

563*

545*

• ■

*

658*

• •

• •

1,035*

1917 1918

# m

Not available.

1918- 1919

1,143

45

1,198

Total smears from extra-metropolitan ports, 2,750. Nil positive for B

pest is.

1919- 1920

1,365

56 1

1,421

.. 1

. .

•• 1

810* f

•• 1

-- 1

1

262*1

..

• • !

.. 1

326*1

• *

I

• •

836*

1920- 1921

Total examinations of plague specimens from Brisbane and Northern Seaport towns

: 3,826, all negative.

Gladstone.

Bockhampton,

Mackay.

Bowen.

Ipswich.

Fiscal Year.

1st July to 30th June.

Bats.

Mice.

Total.

In

fected.

Bats.

Mice.

Total.

In

fected.

Bats.

Mice.

Total.

In

fected.

Bats.

Mice.

Total.

In

fected.

Bats,

Mice.

Total.

In

fected

1909 1910

14

2

16

3,149’

458

3.607

1,358*

5

333

333

1910 1911

• ,

4,635

704

5,339

1,510

728

728

1911- 1912

5,158

556

5,714

a *

a «

1912- 1913

4,073

189

4,262

1,144*

a a

1913 1914

81

3,945

104

4,049

826*

96*

1914 1915

, a

m «

298*

566*

a a

1915-1916

. .

• •

1,276*

515*

97*

1916 1917

. a

• •

389*

556*

a «

1917- 1918

. .

Not available.

1918 1919

Total

smears from extra-metropolitan ports, 2,750 Nil positive for B. pestis.

1919- 1920

182*

• •

. .

104*|

• •

• •

• a

a .

a *

a a

. a

1920- 1921

See above

* Smears examined at Laboratory of Microbiology, Brisbane, t Species of rodents not available.

Table 49.

S \ecies of Rodents Recorded at Brisbane, 1909-1912, and at Townsville, 1912-1915.

Fiscal Year.

M.

decumanus.

M.

rattus.

M.

\alexandrinus.\

1 i

Total.

Brisbane

1909-1910 .. ..

13,075

3,037

5,367

21,479

1910-1911 .. ..

20,121

2,971

4,247

27,339

1911-1912

9,540

1,497

1,364

12,401

Townsville—

1912-1913

1,115

259

73

1,447

1913-1914

2,509

117

273

2,899

1914-1915 . . . .

2,005

140

145

2,290

Notification of Cases of Plague on Shore.

Section 87 (e) of the Commonwealth Quarantine Act 1909 provides for “notification to a quarantine officer of each case of a quarantinable disease which arises in Australia, or within any specified part of Australia, or within any quarantine area/’

Regulation 58 (a) prescribes that “ every medical practitioner in Australia, on becoming aware of or suspecting the existence of quarantinable disease affecting any of his patients in any part of Australia shall immediately report the case by telegram or by the speediest means available to the Chief Quarantine Officer in the State in which the case occurs.”

“ Quarantinable diseases ” are defined as meaning plague, cholera, yellow fever, typhus fever, or leprosy, or any disease declared by proclamation.

in addition, under the several State Health Acts, plague is a notifiable disease.

During the period 1910-1920, no confirmed case of plague occurred. Two suspected cases, negative on bacteriological examination, were reported in Queensland in the fiscal year 1910-11, and in the reports of the Laboratory of Microbiology, which are contained in the Annual Reports of the Commissioner of Health for Queensland, the following examinations of specimens for human plague were reported

Table 50.

Report for year ended.

Specimen.

Number. Result of

Examination.

30th June, 1910

Lymph

Sputum .. .

S All negative

1911

Viscera

From two suspected cases

Negative

1913 . .

Agar culture . . . Blood and lymph

1 .. 1 „

1916

Blood and culture Human* (no other record)

. . 1 o

1919

Sputum

!! i ..

CHAPTER XXIV.

Plague on Vessels in Australia, 1910-1920.

Tlic adoption of uniform quarantine practice in all ports of Australia under the control of Commonwealth Quarantine Service resulted in the compilation of uniform records, and, therefore, the histories of vessels quarantined for plague during this period are for the most part complete. Quarantine of vessels for plague was reported on six occasions, one vessel having cases of plague on hoard on three different voyages, while three vessels were handled in quarantine as under suspicion for plague. The histories of these quarantines are set out hereunder

1912. Taiyuan (steamship of 1,439 tons.    Crew—13 European,

31 Chinese.    Passengers—3 second cabin, 10 steerage. Total souls on

board, 87).—This vessel left Hong Kong on 15th May, 1912, calling at Manila (18th May) and Zamboanga (20th May), and arrived at Darwin on 26th May. On inward medical inspection by the quarantine officer at Darwin, the surgeon of the vessel reported two cases of illness, one of mumps in a Chinese child, cetaiis 2, and a case of cellulitis of the supraclavicular region in a Chinese fireman, cetatis 39, who had joined the vessel at Hong Kong on 14th May. This latter case had a temperature of 103 degrees, and had been sick since 23rd May, hut his general condition was reported on by the quarantine officer as “ quite well.” He was landed for surgical treatment, together with the case of mumps, into isolation at the Darwin Hospital.

After the departure of the vessel for Thursday Island, the question of the case of cellulitis being one of plague was raised, and on examining a smear from the abscess, bacilli resembling B. pestis were seen, and confirmed on cultural examination. The case was quarantined in an isolated hut at the hospital. He developed pneumonic symptoms on 28th May, and died on 29th May. Post-mortem examination showed a double pneumonia, smears from the cut lung showing B. pestis abundance. The spleen was enlarged. The body was cremated, and action taken to prevent any spread of infection at the hospital. The case of mumps from the vessel proved definitely to he one of a double parotitis, and there was no question of plague.

The vessel arrived at Thursday Island on 29th May, where the quarantine officer, having been advised by telegram of the circumstances at Darwin, ordered the vessel into quarantine. Full medical inspection showed no further illness on board. The crew’s quarters were fumigated with sulphur and washed down with a carbolic solution. Cargo was lightered, and local passengers landed to the quarantine station for disinfection and detention for the prescribed period of seven days. Careful inquiry did not reveal any evidence of infected rodents on board.

The vessel called at Cairns (31st May), and at Townsville (1st June), medical inspection at the ports showing no further case of illness. At Townsville, cargo, mails, and baggage were lightered and fumigated, and two local passengers released under surveillance after personal disinfection. The vessel left in quarantine on the following day for Sydney direct. On passing Cape Moreton on 4th June, the master reported by signal “ all well.”

On arrival at Sydney on 5th June, the vessel was kept in the stream. Medical inspection showed no further illness, and passengers were released under surveillance. A thorough search for rats was instituted. Sulphur fumigation was carried out in the holds for seventeen hours, and in the forepeak, seamen’s and firemen’s quarters, and second and third-class accommodation for eight hours. Saloon and first-class cabin accommodation and officers’ quarters were fumigated with formaldehyde gas for six hours. No dead rats were found after fumigation. One rat caught on trapping was examined, and found not infected. A bag of peanuts in No. 1 hold only showed signs of rat infestation and was burnt. Cargo was then discharged into lighters, and the vessel, after taking in coal, left for Melbourne.

The vessel arrived at Melbourne on 10th June. Medical inspection showed no sickness on board. The discharge of cargo was closely supervised, and rats watched for without result.

The bills of health for this voyage showed that for the week ended '13th May Hong Kong reported 149 cases and 132 deaths from plague.

1913. Taiyuan. (Crew—12 European, 62 Asiatic. Passengers— 13 saloon, 19 second, 19 third cabin, 20 deck. Total souls on board, 145).—The history of this voyage showed that the vessel arrived from Australian ports at Hong Kong on 24th April, 1913, and discharged cargo into lighters in the stream. On 26th April, the vessel proceeded to Taikoo Hock, and remained in dock until 7th May. The vessel then proceeded to an anchorage in the stream, and was fumigated with sulphur for twelve hours when empty (holds and crew’s quarters) on 8th May. Cargo was taken on from lighters, and the vessel left Hong Kong on 10th May, called at Manila on 14th May, and Zamboanga (15th-16th May), and arrived at Darwin on 21st May. On 18th May, a Chinese fireman had complained of headache and constipation, temperature 104 degrees, and there was enlargement of the femoral and inguinal glands on both sides. He gave a history of syphilis ten years previously. He was isolated on board. On arrival at Darwin (21st May), his temperature was 103 degrees, and a smear taken from the glands was negative for pestis. Pratique was limited, and cargo and mails were landed and disinfected without direct communication between ship and shore. One local passenger was landed under surveillance. The vessel left Darwin on 22nd May, and arrived at Thursday Island on 25th May.

The patient had a normal temperature and pulse, and showed no prostration, but the glands in both femoral and inguinal regions were enlarged, without tenderness, redness, or oedema. A smear from a puncture was negative. Another member of the crew, a Chinese storekeeper cetalis 33, had had a temperature of 102 degrees, sick since 20tli May, but without other suspicious symptoms. He was isolated on board. He had occupied the same quarters as the original case in the firemen’s quarters amidships with 16 other men. His bunk was near the entrance, that of the original case in the middle, against a bulkhead. The ship sailed the same day without touching at the port, mails being disinfected and landed by launch, and ten local passengers landed under surveillance.

On 26th May, a Japanese passenger who had landed at Thursday Island from the vessel, developed a temperature of 104 degrees with enlarged femoral glands. He was isolated, and the other passengers detained at the quarantine station. On 27tli May, three more of the contacts developed temperatures over 100 degrees, common ailments being excluded and glands shown enlarged in all. On bacteriological examination, bipolar staining organisms could not be demonstrated, hut the quarantine officer made a provisional diagnosis of 'l pestis minor.”

The Chinese storekeeper on the vessel developed enlarged femoral and inguinal glands, but on arrival at Townsville, on 28tli May, these ttvo cases on board showed normal temperatures and nothing except some slight indication of the femoral glands. These two cases, together with fourteen local and over-carried Cairns passengers, were landed at the quarantine station. Third-class accommodation and crews’ quarters were fumigated, and cargo and mails lightered for fumigation. The vessel sailed in quarantine direct for Sydney on the night of 28tli May. Smears from gland puncture in the two cases landed were negative for pestis.

The vessel arrived at Sydney late on the evening of 2nd June, and proceeded to the quarantine anchorage on the morning of 3rd June. Full medical inspection was carried out with a glandular examination of all Chinese crew and passengers. USTo cases of illness were shown on hoard. European passengers were bathed and disinfected with their effects and were released under surveillance. The Chinese passengers were landed into detention at the quarantine station. The holds of the vessel were fumigated and the cargo lightered. A careful search discovered only one rat, which was negative for plague infection on examination. The vessel left for Melbourne on 8tli June without any subsequent development. The original cases, which had been landed at Townsville, convalesced without complications.

The sickness which had developed amongst passengers landed at Ihursday Island did not extend to other contacts. The original case

amongst these passengers developed haemorrhages from the mucous membranes of the mouth, conjunctiva and sclera of eyes, with a subcutaneous hyperoemia, dusky in appearance, obliterated by pressure, over both extremities. By 30th June, however, his condition had improved, the glands resolved, and he quickly recovered. In the other three cases the temperature remained up for a few days, but fell as the glands resolved. Leucocytes only were demonstrated in further smears from gland puncture.

The passengers held in quarantine detention were released at each port on expiration of the quarantine period of seven days.

There was a marked decrease in plague registered in Hong Kong during 1913—108 cases occurring, compared with 1,847 in 1912, and 249 rodents found infected, compared with 390 in 1912.

1914. Taiyuan, (Crew—11 European, 63 Asiatic. Passengers—2 saloon, 7 second cabin, 39 steerage. Total souls on board, 122).—On this voyage this vessel was fumigated with sulphur for twelve hours at Hong* Kong on 7th July, 1914, and sailed from Hong Kong on lltli July, calling at Manila on 14th July, and at Zamboanga on 16th July. On the morning of 14th July, a Chinese fireman reported sick with a temperature of 105.8 degrees. On 15th July, his temperature was 104 degrees, pulse good, and he was diagnosed as a case of typhoid fever. On 16th July, at Zamboanga, his condition was unchanged, and he was landed to hospital,- where, on the following day, a diagnosis was made of septicsemic plague. The case proved fatal. The vessel left Zamboanga on 18th July without disinfection, excepting fumigation of the crew’s quarters by the ship’s officers on 17th July. The vessel arrived at Thursday Island on 25th July. ATo sickness was found on hoard; but, in view of the history of the voyage, the vessel was quarantined and cargo lightered for fumigation, and passengers and their effects released under surveillance after disinfection. The vessel left Thursday Island on 26th July, and arrived at Townsville on 29th Juhg where no further sickness was found. Five local passengers were landed under surveillance, and baggage and mails disinfected. The vessel left the same day for Sydney, after taking in water. On arrival at Sydney, on 3rd August, full medical inspection and glandular examination of all Asiatics showed no further sickness on board. Cargo Avas lightered under close supervision, and the vessel Avas fumigated throughout AAdien empty. Ho rats Avere found, nor traces of rat infestation in the closely supeiwised cargo. Melbourne cargo AAras reshipped, and the A^essel sailed for Melbourne AATithout later developments. The bills of health carried on this voyage shoAved that Hong Kong, for the Aveek ended 8th July, had 21 cases and 17 deaths from plague, and Zamboanga AA^as clean. During this year, Manila reported only scattered cases of plague, 26 in all for the whole year, aat1 tli 29 infected rodents among 118,282 examined.

Suspected Plague an Vessels.

1915. Empire (Steamship, 4.496 tons).-—This vessel had left Melbourne, Sydney, and Newcastle on an outward voyage, and on arrival at Brisbane, on 2nd September, 1915, signalled for the quarantine officer in the bay. A Chinese, number one boy on the steward’s stall’, had eleven days previously developed illness with headache, pain in lower abdomen, with enlarged gland in left inguinal region. On examination, on 2nd September, temperature was normal, a superficial inguinal gland on the left side was enlarged to the size of a son all lien-egg, tender, skin reddened, no fluctuation. Several glands in the femoral chain were palpable. There Avas no obvious lesion present in the area of drainage of these glands. The case was landed to the quarantine station pending the result of a laboratory examination of a gland puncture. European passengers and crew were released under surveillance. An inspection for signs of rats was made, and only a very feAV and slight traces of infestation Avere found in the quarters. The vessel Avas allowed alongside to Avork cargo, and on the receipt of a negative report from the laboratory in regard to the case, all quarantine restrictions Avere raised and the case returned on board.

Mataram (Steamship, 3,278 tons).—This vessel, from Singapore, via Soerabaya and Darwin, arimped at Thursday Island on 12th November, 1915. One Malay member of the creiv Avas reported to be suffering from strangulated hernia. He Avas first seen by the surgeon on 11th November, Avlien he had a temperature of 102.5 degrees, pulse 103, Avith spasmodic pain about the umbilicus and/over the SAvelling. On exami-tion by the quarantine officer, on 12tli HoA^ember, his temperature Avas 99.9 degrees, pulse 95, and there Avas a hard round SAvelling the size of a goose-egg in the right inguinal region, firmly fixed to structures behind, and not palpable through the inguinal canal. There Avere hard discrete glands in the left groin. There Avas no local lesion to account for a glandular SAvelling. His general condition Avas excellent. As pestis ambulans could not be definitely excluded, pratique Avas limited, and no communication Avas alloAved betAveen the vessel and shore. Cargo Avas lightered and fumigated, and one passenger landed for release under surveillance. The case was landed to the isolation ward at the hospital. An incision Avas made in the SAvelling, and revealed a homogenous bound-doAvn mass of glands Avith small collections of pus. There Avas no haemorrhage into the glands or surrounding tissues. A smear from the glands Avas negatiATe for pestis. From 16th Xovember, the temperature declined, and the glands drained and subsequently healed, the patient only complaining of continued Aveakness. A diagnosis of acute lymphadenitis from a pyogenic organism Avas made. The vessel arrived at Cairns on 14th Hovember, and at Toavus-ville on 16tli ISToAminber. At this latter port, the creAv’s quarters and third-class accommodation Avere fumigated, and cargo lightered. At

Brisbane, on 20th November, there was no further illness on board, and no traces of rat infestation found, either in holds or cargo, on careful search and supervision of discharged cargo. No further developments occurred on the vessel.

Eastern (Steamship, 3,586 tons).—This vessel left Kobe on 22nd October, 1915, after fumigation, and called at Moji (28th October)Hong Kong (lst-4th November), and Hilly, Timor (12th November). The vessel was cleared at Darwin on 14th November, and extended pratique up to Brisbane granted at Thursday Island on 17th November. 'The vessel, therefore, arrived at Cairns on 20th November without inward medical inspection. After arrival, Mrs. G. B., a second-class female passenger, reported to the surgeon with pain in the groin. She had previously reported, on 17th November with pain in the pelvis and scalding on micturition, relieved on treatment. She had come from Shanghai, and boarded the vessel at Hong Kong on 3rd November. 'The case was reported to the quarantine officer at Cairns, who found the woman suffering from an inflamed and tender gland in the left inguinal region, temperature 98.8 degrees. He ordered the vessel into quarantine to proceed to Townsville, whore on arrival, on 21st November, the bacteriological examination of a smear from a gland puncture was negative. Pratique was granted for that port, and the vessel left for Brisbane on 22nd November.

On 22nd November, the quarantine officer, Cairns, reported that a Russian female, Mrs. E., a third-class passenger, who had landed from the vessel, was reported ill at a local hoarding-house, with a temperature of 99 degrees, pulse 100, and a large inflamed tender gland in the groin, without any obvious lesion to account for it. 'The case was removed to the isolation hospital, and the boarding-house quarantined.. Cargo from the vessel was traced and fumigated, and a vigorous rat campaign initiated. Contacts were disinfected and released under surveillance. A smear from gland puncture of the case proved negative, and this was verified on subsequent examination at the Australian Institute of Tropical Medicine. Townsville.

The vessel arrived at Brisbane on 24th November, and was again ordered into quarantine. Mrs. G. B. was landed to the quarantine station, and local passengers released under surveillance after disinfection. The second, third, and deck passengers’ accommodation and the crew’s quarters were fumigated. Cargo was lightered under supervision, and, excepting packages likely to be damaged, was fumigated. Meanwhile all cargo landed at Queensland ports (Townsville and Cairns) was traced and fumigated, and contacts released under surveillance after disinfection. The vessel left Brisbane for Sydney on 25th November.

On arrival at Sydney, 27th November, a medical inspection and glandular examination of all Asiatics showed no further sickness on

board. Cargo was discharged under supervision, no rats or traces of rat infestation being discovered, nor were any rats obtained on trapping”. Tlio routine fumigation of the baggage of steerage passengers was carried out.

Further examination of Mrs. G. B. at the Brisbane Quarantine Station showed a negative result on examination of a gland puncture. A diagnosis was made of suppurative salpingitis characterized by an intense pelvic inflammation with a vaginal discharge, with secondary enlargement of the inguinal glands. The case was therefore removed to the Brisbane General Hospital.

Vessels were detained in 1911, 1913, 1914, 1915, 1916 on account of members of the crew who, on examination, were discovered to have enlarged glands. Further investigation excluded a diagnosis of plague, and search of the vessels revealed no evidence of rat-plague. In this connexion, it may be noted that considerable diagnostic difficulties often confront the quarantine officers in giving a definite decision in connexion with cases of climatic bubo occurring in members of the crews of vessels from Asiatic ports.

In March, 1918, the s.s. Monloro arrived at Thursday Island from Singapore via Java ports, Koepang, and Darwin. After leaving Darwin six cases of pneumonia, with four deaths, occurred amongst Javanese coolie deck passengers. Special consideration was given with a view to determining the possible risk of plague having been a factor in the pneumonia. Careful investigation at Thursday Island, Townsville, and Brisbane, and the clinical history of the two survivors, appeared to exclude plague with reasonable certainty.

The histories of these vessels show in a clear manner the administrative difficulties which may arise in the control of plague reported on ship-board. Of those three types of vessels which are liable to require treatment for an epidemic or epizootic of plague, under which categories vessels quarantined during the 1900-1909 epidemic were discussed (page 78), the Taiyuan, in 1912 and 1914, came within the first category, the cases having possibly been infected on shore. It is worthy of notice, however, that in the 1912 quarantine the illness is reported to have developed eight days after the vessel left TIong Kong, and nine days after the man had joined the vessel. This 1912: quarantine is the only instance in which bacilli pestis Avere demonstrated in Australia, either in man or rodents, during this period. ISTo vessel during this period comes within the second category, vessels on Avliicli epizootic occurred Avithout cases in man. Of the third category, over this period of eleA'en years there is no clear-cut history of a concurrent epidemic and epizootic on board vessels, such as occurred on the Burwali and Eulomene in Australia in 1900 and 1902, or such ns has been reported on several occasions on vessels making the longer

C.5T6'.)—-5 voyage from the Orient to Europe. In the 1913 quarantine of the Taiyuan, if the cases be accepted as cases of plague, evidence would point to a focus of infection on board, but the occurrence of an epizootic on board, or the presence of infected fleas, cannot be determined. It is significant that on each of these three occasions the vessel left Hong Kong during the months of May or June.

Of those cases of suspected plague on the three vessels concerned, plague can be ruled out on reviewing the histories of these quarantines, although the administrative measures adopted at the time can be endorsed as necessary.

In 1919 the port health officer at Bombay reported that the s.s. Malta arrived at that port on 26th March, 1919, with one of the crew suffering from plague of 18 hours’ duration, and with rats dying in large numbers in Ko. 1 hold. The rat mortality was proved bacteriologically as due to plague. The vessel had come from Wellington, Kew Zealand, via Sydney (26tli February), Newcastle (28tli February), Fremantle (9th March)} and Colombo '(29th March). At Sydney the vessel had loaded 200 tons of wheat from lighters in the stream, and coaled from lighters at Colombo. The recent epizootic on arrival would indicate that infection in this instance had come on board the vessel at Colombo.

It is shown on page 119 that no evidence of an epizootic was determined on any vessels calling at Australian ports during this period. Either, then, no such rodent infection was present, or the measures adopted were insufficient to detect the presence of such infection on board. This point will be discussed at a later stage, when the origin and course of the 1921-1922 outbreak can be reviewed.

CHAPTER XXV.—PLAGUE IN OVERSEA COUNTRIES.

This period under discussion saw a marked strengthening in the quarantine liaison which had developed between the health services of different countries. The Office International d’Hygiene Publique,    which had been    instituted in 1907    under the

terms of the International    Sanitary Convention    of Pans,

served as a central clearing house for quarantine intelligence. The British    Local Government Board (which became the

Ministry of Health in 1919) and the United States Public Health Service were enabled by reports from their consular services to compile valuable publications, which disseminated information as to the progress and diffusion of the quarantinable diseases throughout the world. The reviews by Dr. R. Bruce Low, of the British Local Government Board, were of especial value from the epidemiological view-point, although their late compilation limited their value from the quarantine aspect. In Australia, information received from these sources or extracted from bills of health brought by vessels from oversea countries was, from 191(1 onwards, forwarded to quarantine officers as a fortnightly bulletin.

It has been shown on page 13 that the introduction of plague into Australia in 1900 coincided with a world-wide quickening up of the pandemic spread, which had commenced in 1896. For the years which preceded the 1921 outbreak it is not possible to show such a dramatic extension of plague, but nevertheless there was an antecedent lighting up of plague infection, particularly in the Far East. Most striking, although of doubtful significance from the epidemiological view-point in this connexion, was the epidemic of pneumonic plague which swept through Manchuria in 1920-21, and spread, in 1921, to Vladivostock. In this latter port, in 1921, two cases of bubonic plague and five infected rodents were also discovered, possibly introduced, however, from oversea. In Turkestan,. there was, in 1921, a notable incidence. In British India, following the severe epidemic years of 1917-18, plague had appeared to wane, and although the 1921 “ plague year ” was one of the mildest on record, the decline was most marked in those districts which in previous years had suffered most severely. In those districts where plague had been mildly epidemic only, the decline was less appreciable. In French Indo-China, although not assuming large proportions, definite outbreaks occurred early in 1921, involving the ports of Haiphong and Saigon. In Europe there was little change, but in Russia there was some evidence-of development and extension of infection, which later culminated in definite outbreaks. In the endemic centres in America and Africa, plague persisted with little change or extension. In Mauritius, plague made a reappearance in May, 1921, and developed into a sharp epidemic. In Ceylon, first infected in 1914, plague had declined

markedly, and possibly died out in 1919 (87 cases over seven months). In 1920, however, 235 cases occurred, and although the number of reported cases is small, infection has since persisted. In Java, despite strenuous and well-applied measures of eradication, plague, which had declined since 1914, in 1918 caused 733 deaths; in 1919, 2,954 deaths; in 1920, 8,918 deaths; and in 1921, 9,727 deaths; the most severe infection occurring in districts in mid-Java. In Hong Kong and the China ports, plague persisted in endemic form, with occasional outbreaks in the latter ports, the usual maximum incidence being in the months of June and July. It is significant that this period of maximum plague incidence in the Far East precedes the season of maximum risk in Australia, as evidenced by the experience of the previous outbreaks and the history of vessels quarantined for plague in Australian ports.

Summary or Human and I to dent Plague Infections 1921-1922

Epidemic.

Human Plague.

liodent Plague.

. —

Number

of

cases.

1

Deaths.

Date of first human case.

Date of last human case.

Number

of

infected

rodents.

Date of first

infected

rodent.

Date of last

infected

rodent.

Queensland

116

63

21.8.

I

21

13.3.

22

306

31.8.

21

31.10

22

Brisbane

58

27

21.8

21

8.3

22

190

6.9.

21

31.10

22

Townsville

33

21

20.9

21

11.1

22

64

19.9.

21

16.11

21

Cairns

18

11

4.10

21

5.12

21

18

31.8

21

18.2

22

Port Douglas . .

2

1

15.10

21

13.11

21

1

23.11

21

23.11

21

Innisfail

1

Nil

1.11

21

1.11

21

4

17.11

21

17.11

21

Ipswich

1

1

12.12

21

12.12

21

2

4.10

21

7.10

21

Bundaberg

1

1

25.2

22

25.2

22

Nil

Aramac

1

1

13.3

22

13.3

22

Nil

Toowoomba

1

Nil

18.10

21

18.10

21

Nil

Maryborough . .

Nil

Nil

2

13.10

21

23.10

21

Rockhampton . .

Nili

Nil

5

26.9

21

18.2

22

Ingham and Dis-

trict

Nil

Nil

20

12.10

21

12.1

22

New South Wales

Sydney

35

10

29.11

.21

9.6

.22

151

19.9

21

13.7

.22

(ex ss.

Wyreema)

Total for Australia

151

73

21.8.21

(Brisbane)

9.6.22

(Sydney)

457

31.8.21

(Cairns)

31.10.22

(Brisbane)

PART III-PLAGUE IN AUSTRALIA, 1921-1922.

CHAPTER XXVI. COMMENCEMENT OF THE EPIDEMIC.

On 13tli September, 1921, the Commissioner of the State Public Health Department, Queensland, notified the Director-General of Health, Commonwealth Health Department, of a death from plague which had occurred in Brisbane on 23rd August, 1921, the diagnosis having been bacteriologicsdly confirmed. A rodent crusade has been initiated by the State authorities, and up to 13tli September spleen smears in five rats from tvo produce stores in Brisbane showed plague bacilli. The produce stores were some distance apart, one in South Brisbane, one in North Brisbane. On 16tli September an infected rat was found at stables in North Brisbane, more than a mile from the nearer of the two produce stores. On 16th and 17th September one infected rat was found each day at the produce store in North Brisbane.

On 18th September seven infected rats were found at widely-separated points.

The first case of plague was a workman employed at a produce store which was found to be free from rats, but which was adjacent to the North Brisbane produce store at which plague rats were found on 13tli, 16th, and 17th September.

The varieties'" of rats found infected up to this stage comprised—

Battus rattus rattus

10

Rattus norvégiens

6

Unclassified

1

Tiie first stage of the outbreak then may be summarized as follows:—

On the 23rd August, 1921, a man fell ill with plague, and no fuxtlier case occurred until 21st September, In the meantime rodent plague attacking both rattus and deeumanus was discovered in several premises which, as will be seen from the map facing page 204, were separated from each other by considerable distances.

Sydney.-—0\\ 19th September. 1921, s.s. Wyreema from North Queensland ports via Brisbane, arrived at Sydney, having sailed from Brisbane on 17th September. The cargo was discharged under supervision, and, during unloading, six dead rats were found in No. 4 hold. 4

Of these one was found to be plague-infected (bacteriologically confirmed) the remainder being too putrescent for examination. The vessel was further fumigated before any more cargo was removed, and after fumigation twenty dead rats were found, of which eleven were infected. At the conclusion of unloading the Wyreema, and after terminal fumigation, 70 dead rats were found, making a total of 142 found in the vessel.

Townsville.—On 19th September the quarantine officer, Townsville, reported the presence of a number of dead rats on s.s. Kuranda at Townsville. The health inspector at Townsville also reported dead rats in a local store, which on examination proved to be infected. The rats from the Kuranda had been thrown overboard, and were not available for examination. On 24th September, however, two rats found on this vessel proved to be infected. The vessel had not been in Brisbane since April, 1921.

Brisbane.—On 19th September two, and on 20th September one, infected rats were found, the last-mentioned in a dwelling house 2 miles from any previously known infected premises. On 21st September a further infected rat Avas found in a suburban dwelling house. On 21st September also, the second human case of plague occurred, a female cleaner in a city office.

S.s. Levuha reported from Mackay that two dead rats had been noticed on the vessel at Brisbane on 9th September, and subsequently, while discharging cargo at Mackay, Bowen, ToAvnsville. and Cairns, dead rats were seen in the holds. The vessel Avas ordered to Brisbane, the cargo lightered under supervision, and the vessel fumigated. No infected rat Avas found, but eight dried carcases were found in the fruit holds. The conditions on 23rd September suggested that there had been on the vessel an epizootic of rat plague for about three Aveeks, and that this had come to an end.

Brisbane.—Infected rats, all rattus noiwegicus, Avere found in Brisbane as follows:—

D


Nil

1


21st September, 1921 22nd September, 1921 23rd September, 1921 24th September, 1921

Townsville.—On 22nd September, 1921, a case of human plague (a girl) was reported from Townsville.

Cairns.—On 23rd September, 1921, the Commissioner of Public Health, Queensland, reported that a rat-spleen smear from a rat caught near the wharf on 31st Au^st showed plague bacilli. Another rat caught on 12th September on the Esplanade was infected.

S.s. Bomb ala.—One plague-infected rat was found dead in the holds of the vessel at Townsville during the discharge, under supervision, of the cargo, on 23rd September. After unloading and fumigation 60 rats were found, three of these being infected.

S.s. Wyandra was fumigated at Sydney on 23rd September. After fumigation 212 dead rats were found, none being infected.

Sydney.—On 21st September, 1921, two rats, caught at the Lime-street wharf, were found to be infected. On 22nd an infected rat was found dead under this wharf: on 23rd one further infected rat was caught at this wharf.

The s.s. Wyreema (vide supra) had berthed at this wharf from 8.40 a.m. to 3 p.m. on 19th September.

Brisbane —The particulars of rat destruction and examination in Brisbane as reported by the Queensland Department of Health for the period 3rd to 24th September, 1921, were as follows:—

In all 4,935 rats have been destroyed, and of these 4.269 have been examined. Twenty-eight of the plague-infected rats were as follow:—

Before 15th September, 7—2 (R.B.B.), Roma-street.

3 (R.R.R.), Roma-street.

2 (1 M.R.R.), South Brisbane.

(1 R. X.), South Brisbane.

15th September—-1 (R.X.), Roma-street.

1 (Unclassified), Valley.

16th September—1 (R.XA, South Brisbane.

17th September—2 ((R.X.), Ann-street.

1 (R.R.R.), Ann-street.

1 (R.R.R.), Valley.

1 (R.R.R.), Valley.

1 (R.X.), South Brisbane.

1 (R.R.R.), South Brisbane.

18th September—Xil.

19th September—-1 (R.R.R.), Roma-street.

1 (R.X.), Roma-street.

20th September—1 (R.X.), Ascot.

21st September—1 (R.X.), Ivelvin-grove.

1 (R.R.R.), Burnett-lane.

22nd September—1 (R.R.R.), Roma-street.

1 (R.R.A.), Eagle-street.

1 (R.X.), South Brisbane.

1 (R.X.), Kangaroo Point.

1 (R.X.), Red Hill.

23rd September—Xil.

24th September—1 (R.X.), South Brisbane.

25th September—Xil.

26tli September—1 (R.U.L Edward-street.

1 (R.H.). ETortli Quay.

27tb September—1 (M.M.), Roma-street.

4 (R.R.R.), Enoggera.

1 (R.R.R.), Edward-street.

1 (R.LL), Queen-street.

1 (Ibis’. L Soutli Brisbane,

28tli September—ISTil.

29tb September—1 (R.R.A.), Roma-street.

30tli September—ISTil.

Townsville.—On 25tli September, 1921, it was reported that 53 rats taken in Townsville liad been examined. Of these fourteen were infected and two doubtful. The infected rats were obtained at premises situated within one block in the town. On 27tli four, and on 28tli three further infected rats were found out of a total examined on tlie two days of 23. Up to 30tli September, 28 infected rats were found out of a total of 182 examined.

Sydney.—On 24tli September one infected rat was caught at premises opposite tlie lime-street wharf. On 26th September a second infected rat was caught at these premises. On 27tli two infected rats were caught at the .Lime-street wharf, making a total of six infected l ats found at this wharf since 20tli September in a total of 31 examined.

On 28tli three further infected rats were found at this wharf and two at the premises opposite.

ISTo infected rats were discovered in any other part of Sydney; the infected area being very circumscribed in the immediate neighbourhood of Lime-street wharf.

Brisbane.—On 30th September the third human case of plague occurred in Brisbane. The patient was a boy, five years old, living at Spring Hill.

Rockhampton.—Three rats (R.U.) found on 26th and 27th September were infected.

Townsville.—One infected rat found on 30th September.

There are several features of great epidemiological importance in connexion with this invasion period. The account given above lias been set out in chronological order with the object of emphasizing the rapid sequence of events at this time.

The first reported case died on 23rd August, 1921. A careful search of death certificates for the previous weeks disclosed no evidence to suggest that other cases had been missed. The onset of the illness in this first case was probably on 21st August. Allowing for incubation period it is probably reasonably accurate to assume that this patient was actually infected from a week to ten days before 23rd August. It is evident then that rodent plague must have existed in Brisbane at the middle of August.

There hud been nothing prior to this which had attracted notice to the possibility of rodent plague.

By 13tli September it had been demonstrated that rodent plague existed in two produce stores situated about 1 mile apart, and on 18tli September the more extensive search instituted revealed, as is seen from the map facing page 201 that rodent plague was widely distributed in the city.    ,

It is a general rule, well enough established by experience, that epizootic plague precedes epidemic plague, and it is also a common experience that the first human case does not usually occur until the rat epizootic lias become well established. In the present instance the cessation or partial suspension of routine rat-suppression Pleasures in Brisbane removed all possibility of evidence as to the condition of the rat population during July ana August, or even earlier. The experience in Brisbane during the invasion stage (1900) of the last plague epidemic in Brisbane was (Plague in Queensland—Ham) that “ the incidence of rat plague in Brisbane rose steadily during June and July, reaching its maximum in August.” It is, however, improbable that the same course was followed on this occasion. All that can be said is that rat plague existed in Brisbane for a shorter or longer, but uncertain, period prior to the middle of August.

A plague-infected rat was caught at Cairns on 31st August, and there was evidence that a plague epizootic had commenced on s.s. Levuka in the first week in September. It is clear, therefore, that by the end of August rat plague in Brisbane had become active enough to infect the coastal shipping, which, it may be presumed (although no direct evidence has ever become available) in turn infected the northern port of Cairns.

This activity became more pronounced during September. A definite plague epizootic was established on s.s. Kuranda by 19th September, on s.s. Wyreema by 19tli September, and on s.s. Bomb ala by 23rd September. There is considerable significance attachable to the outbreak on s.s. Kuranda, as this vessel had not been in Brisbane since April, 1921, but was trading between Townsville and Cairns. Plague was definitely established in epizootic form in Cairns by 31st August, in Townsville by 19tli September, in Rockhampton by 26th and 27th September, and in Sydney by 21st September.

The only other localities infected throughout the whole period were Maryborough and Ingham, in neither of which was there any human case; Ipswich and Innisfail (with one human case each); and Port Douglas (two human cases). The dates of the discovery of the first infected rat and the total numbers of infected rats are as follows:—

2 infected rats.

20 „

2

»

4 „

yy

1 „

yy


4th October, 1921, Ipswich . .

12th October, 1921, Ingham . .

31st October, 1921, Maryborough 17th November, 1921, Innisfail 23rd November, 1921, Port Douglas

Taking the middle of August as a known starting point, rat plague had become established in Cairns within three weeks, and within six weeks had taken firm hold of all the principal ports along nearly 2,000 miles of coast line. Assuming, as is legitimate, that some days after the introduction of infection must elapse before dead rats are observed in local stores, the infection must have been introduced into Cairns and A.uwuisville within the days preceding 31st August and 19th September respectively. The case of human plague in Brisbane was known on 23rd August, but was not declared officially until 13th September. This was the period during which infection possibly, or even probably, left Brisbane for Cairns and Townsville. This rapidity of spread of plague infection over long distances in a short time, emphasizes the necessity for immediate action upon verification, and even upon suspicion, of plague in man or in rodents.

The Origin of the Infection.

There are two alternative hypotheses as to the source of the infection—either it was introduced into Australia from abroad, or it had remained present since the last recorded rat plague in 1910, in a condition of low infectivity and mild virulence, until under the influence of some factor it had become more active in respect of both infectivity and virulence.

In Chapter XXV. it was shown that—

(a)    Plague had between 1918 and 1921 become somewhat more

active throughout the world, a condition similar to that in 1899-1900 when the previous epidemic began;

(b)    Regular and extensive rat destruction with post-mortem

examination had been continued in Sydney since 1910 without any revelation of the existence of plague infection ;

(c)    Similnr rat-control measures had been sustained in Brisbane

for the earlier part of the same period, but had in the years just preceding the outbreak been barely maintained. Xevertheless, there was no sign of rat plague in Brisbane.

(d)    There had been maintained systematic and regular rat

control measures on all ships from overseas;

(e)    There had been only two ships with human plague on board

arriving in Australia, and in no ship was there discovered any sign of rat plague.

All that can be said is that the infection may have persisted from the previous epidemic, or it may have been introduced from overseas; and that the argument against either alternative is precisely the same in each case—that, in spite of rigorous and systematic search patiently maintained over the long series of years no plague-infected rat was identified either on shore or on incoming vessels.

CHAPTER XXVII.—THE SPREAD WITHIN THE CITY OF BRISBANE.

A comparison of the two maps shown facing page 204 will illustrate the extent of rodent plague in Brisbane by 24th September, 1921, eleven days after the existence of rat-plague had become known. It is very improbable that the spread took place within that period—it is, on the contrary, most probable that rodent plague had become widely distributed throughout the metropolitan area some considerable time before it was recognized, and that the extent of its spread was revealed as the search proceeded.

This provides a convincing demonstration of the necessity for unceasing vigilance and activity in conformity with those standards of rat control and rat proofing now universally accepted; or, at the least, for an intelligence service sufficiently efficient to be depended upon to

detect, at a very early stage, the presence of rodent plague.

/

The subsequent course of the epidemic and of the epizootic in the metropolitan area of Brisbane is shown by the tables hereunder, in which are set out:—

(a)    The details of each verified human case.

(b)    The details of rodents destroyed, examined, and infected.

(c)    The parallel course of the epidemic and epizootic in weeks.

Table 51.—Metropolitan Area of Brisbane. Human Cases of Plague.

No.

Date

reported.

Name.

Age.

Sex.

Occupation.

Address.

By whom reported.

Date of Onset.

Date

Isolated.

Susp.

or

Pos.

Dis

charged

cured.

1

23.8.21

W.H.L.

• •

M

Employee, Denham Bros.’ Produce Store, Roma-st.

Roma-street

C.P.H.

21.8.21

• ♦

P

• •

2

21.9.21

L.G.F. ..

32

F

Office cleaner

Mary-street, Long Hill, Kelvin Grove

C.P.H.

20.9.21

21.9.21

P

• •

3

30.9.21

P.S.

5

M

Home .

44 Birlev-street, Spring Hill

C.P.H.

29.9.21

30.9.21

P

5.11.21

4

6.10.21

R.A.R. ..

32

M

Carter

Ipswich-road, Rock-lea

C.P.H.

4.10.21

C.10.21

P

* *

5

14.10.21

B.J.M. ..

59

M

Engine-driver, Laidlaw’s Produce Store, Grey-street

Meri vale-street, South Brisbane

C.P.H.

HI since 7.10.21

14.10 21

P

8.12.21

Date of Death.

23.8.21

21.9.21

8.19.21


Remarks.

First seen by doctor at P.IVf. Employed at Denham Bros.’ Produce Store, Roma*st. Infected rodents found

8.9.21 and 15.9.21, at Addis Bros.’ Produce Store, next door to his place of employment. A number of infected rodents were afterwards found in this block, in which there are numerous produce stores.

Employed at Courier Office, Queen-street, and Desmond C'hrs., Adelaide-street. No infected rodents found in area where employed prior to infection. No infected rodents found in area where residing prior to or after infection.

First isolated at Lytton Quarantine Station. Removed to Wattlebrae Isol. Hosp., 14.10.21. Four human cases subsequently occurred within area of i mile of residence in Spring Hill. See note under Case No. 32.

Smear positive. Employed carting flour from Flour Mill, South Brisbane where infected rodent- were found on 24.9.21,

4.10.21 (2), 0.10.21 (2), 22.10.21 (Ij. No infected rodents were found within 2 miles r-f residence.

Infected rats found at Laid law's Produce Store, September, 1921. Infected rodents vvere also found at a residence in Russell-street about 250 yardc away from his re idenee on 22.9.21 and at Flour Mills, Stanley and tribune-streets, about 200 yards away from residence on 24.9.21,4.10.21, 6.10.21, and 22.10 21.

Human Cases of Plague— continued.

No.

Date

reported.

Name.

Age.

Sex.

Occupation.

Address.

By whom reported.

Date of Onset.

Date

Isolated.

Susp.

or

Pos.

Dis

charged

cured.

Date of Death.

Remarks.

(5

16.10.21

J.D.

27

M

Packer and storeman

Thorrold - street, W ooloowin

O.Q.O. & C.P.H.

14.10.21

16.10.21

P

19.10.21

B. pestis found in smear. Erap'oyed Barry and Roherls, Queen-street, Brisbane. No infected rodents found near residence. Infected rodent was found in block opposite Barry and Robevt? on 21.9.21, i.e., Burnett-lane; one found in adjoining block near Ehzabeth-street and Edwardstreet on 27.9.21. Rodent infected found Harrington s in same block, Queen-°treet, on 4.10.21. One infected rac found at Barry and Roberts’ stables, Stan)ey-streetv South Brisbane, on 12.11.21.

1

17.10.21

G.R.

41 ;

M

Packer and grocer’s assistant

Tingal-road, W yn-num South

C.P.IT.

15.10.21

18.10.21

P

• *

22.10.21

B. pestis found in smear. Same remarks as No. 6. No infected rats found in vicinity of residence.

8

22.10.21

L.A.B. ..

42

F

Home duties

Racecourse - road, Ascot

C.P.H.

18.10.21

22.10.21

P

28.11.21

* •

Bubo developed 20.10 2l. Forty rats found on these premises by rat gang. Nil infected.

!)

23.10.21

W.M.F.

61

M

Chinese cabinet maker

C/o Mee Lee Bros., Wickham - street, Valley

C.P.H.

Not seen illness cal ma

during by medili

P

23.10.21

Smear positive. Confirmed P.M. Date of onset was probably very shortly after 14.10.21. Infected rat found on these premises, 14 10.21, and an infected cat was found at the residence at the rear of these premises, 25.10.21.

10

24.10.21

L.IJ. . .

32

M

Employed at his father’s grocery store, Musgrave-road, Redhill

Boardinghouse, Musgrave - road, Redhill

C.P.H.

22.10.21

24.10.21

P

10.12.21

Right femoral bubo. Smear positive. Two infected rodents found m this street on 22.9.21. An infected rat was found on the grocery store premise3, 28.10.21.

11

25.10.21

J.R.H. ..

35

M

Butcher

Douglas-street, Milton

C.P.H.

24.10.21

24.10.21

(

P

* •

25.10.21

Smear positive. One infected rat found Douglas-street premises, 21.10.21. One infected rat found butcher’s premises at Irving - street, Auchenflower, 26.10.21

12

28.10.21

H.D. ..

49

M

Employed at H. A. Petersens Ld., Seedsmen, Georgestreet

W ilson-street, Ka n-garoo Point

C.P.H.

22.10.21

28.10.21

! - PV'

. P

8.12.21

..

Smear positive. An infected mouse from Petersen’s premises w'as found on 28.10.21. Same block as human case No. 1 (W.H.L.).

Human Cases of Plague—continued.

No.

Date

reported.

Name.

Age.

Sex.

Occupation.

Address.

By whom reported.

Date of Onset.

Date

Isolated.

Susp.

or

Pos.

Dis

charged

cured.

Date of Death.

Remarks.

13

31.10.21

J.C.M.S.

45

M

Ratman, Brisbane City Council

Cr.bb-street, Milton

C.P.H.

30.10.21

31.10.21

P

24.12.21

• •

Smear positive. Occupation, ratman. This would take him into infected areas.

14

1.11.21

E.J.C.C.

42

F

Boardinghouse

proprietress

Morven Boardinghouse, Sandgate

C.P.H.

20.10.21

30.10.21

P

• •

31.10.21

Smear positive. Source of infection not traced. No infected rodents found in locality.

15

2.11.21

Jl.il. . .

55

M

Overseer, Bryce’s stables

Musgrave * street, W est End

C.P.H.

28.10.21

1.11.21

P

13.12.21

Smear positive. A second human case occurred in this same block (Case No. 28) on 20.11.21. No infected rodents iu street.

16

2.11.21

J.R.A.H.

12

M

Schoolboy

Douglas-street, Milton

C.P.H.

29.10.21

1.11.21

P

13.12.21

• •

Smear positive. Son of Case No. 11.

17

2.11.21

S.

25

F

» • •

Cambridge - street, W est End

Dr. Meek

17.10.21

• ■

S

• •

• •

Not verified.

18

3.11.21

C.S.N. ..

71

M

Printer

Main-street, Eagle Junction

C.P.H.

1.11.21

2.11.21

P

3.11.21

Reported by C.P.H. as pneumonic plague. Confirmed post-mortem. No infected rodents in vicinity residence. It appears probable that this man worked as printer in George-street (Nichols, Larwill, and Butler, Printers). Infected rodent found next door at Petersen’s, Seed Merchants, 28.lo.21.

19

7.11.21

Allen C...

42

M

Storeman

Gordon-street, Paddington

C.P.H.

5.11.21

6.11.21

P

13.12.21

Smear positive. Employed W. Siemon and Sons, Produce Merchant, Romastreet, where infected mice were found on 9.11.21 (1), 10.11.21 (1), and 19.11.21 (2).

20

12.11.21

I.D.

31

F

Cook .. ..

York Hotel, Queenstreet

C.P.EI.

10.11.21

10.11.21

P

28.1.22

Smear positive. Infected rodent at Harrington’s, two doors away, on 4.10.21.

21

12.11.21

J.K.

52

M

W illiams’ Coffee Palace, Georgestreet

C.P.H.

7.11.21

10.11.21

P

17.11.21

Smear positive. Premises adjoining cases Nos. 40 and 42, a badly infcc.ed locality. Infected rodents were found at Petersen’s, five doors a'-'ay, 28.10.21, and other places in this locality.

22

14.11.21

V.G.T. ..

6

F

• •

C/o Mrs. Roach, 138 Melbournestreet, S. Brisbane

C.P.H.

1

10.11.21

12.11.21

P

• •

15.11.21

netti jjijmli ve. ¿111.1« .2 1, iii'cteu umcuu

from Holzberger’s Bulk Stores, Melbourne-street, four blocks away.

Human Cases of Plague—continued.

No.

Date

reported.

Name.

Age.

Sex.

Occupation.

Address.

By whom reported.

1

Date of Onset.

Date

Isolated.

f

Susp.

or

Pos.

Dis

charged

cured.

Date of Death.

Remarks.

23

14.11.21

J.L.A. ..

11

M

Schoolboy ..

C/o Mrs. McClure, Kelvin Grove-road, Normanby Hill

C.P.H.

10.11.21

13.11.21

P

31.12.21

Smear positive.

24

14.11.21

W.F. ..

12

M

Schoolboy

Hayward - street, Paddincton

C.P.H.

10.11.21

13.11.21

P

• •

15.11.21

Smear positive.

25

14.11.21

W.E.S. ..

44

M

Cellarman .

103 Roger-street, off Gregory-terrace

C.P.H.

10.11.21

13.11.21

P

* •

17.11.21

Smear posit've. Employed by Brabant and Co., Charlotte--treet, an infected rodent locality.

26

18.11.21

W.H.C.

15

M

Factory hand

Merivale - street, South Brisbane

C.P.H.

17.11.21

18.11.21

P

• •

20.11.21

Employed Dixon’s Tannery, off Montague road, W est End.

27

19.11.21

W ..T.Y. ..

24

M

Chinese ..

Boma-street

C.P.H.

19.11.21

19.11.21

P

• •

21.11.21

Infe< ted rat found at adjoining premises, Balt c Separaior Co., 11.11.21.

28

21.11.21

Carl B. ..

19

M

Labourer ..

C/o Anthony and Buchanan - street, W est End

C.P.H.

20.11.21

21.11.21

P

• •

24.11.21

Employed at Old. Preserves Ld., Vulture-street. Infected rat found at Harper’s Pickle Factory nearby on 15.11.21.

29

23.11.21

H.J.Y.

4/12

M

Infant

Boma-street

C.P.H.

21.11.21

23.11.21

P

23.11.21

Son of case No. 27. See above.

30

24.11.21

T.T.B. ..

40

M

Yardman

Union Hotel, Wick-ham-street

C.P.H.

22.11.21

24.11.21

P

■ •

26.11.21

Infected rats were obtained from the adjoining premises, Parisian Medical Agency, on 1.11 21 and 19.11.21.

Mild plague. Case No. 30 occurred a same premises, 22.11.21. Infected rats on adjoining premises, Parisian Medical Agency, on 1.11.21 and 19.11.21.

31

26.11.21

M w

F

Barmaid ..

Union Hotel, Wickham-street

C.P.H.

21.11.21

25.11.21

4.1.22

32

28.11.21

E.G.

65

F

W asherwoman ..

75 Bradley-street, Spring Hill

C.P.H.

20.11.21

26.11.21

P

28.11.21

Three other human cases occurred in this neighbourhood. Case No. 3, 29.9.21. Case No. 38, 8.12.21. Case No. 104, 25.12.21.

33

29.11.21

M.T. ..

44

F

Boardinghouse

proprietress

C/o Ernest and Meri-vale-street, South Brisbane

C.P.H.

22.11.21

28.11.21

P

28.11.21

Pneumonic plague. An infected rodent from these premises, 16.11.21.

34

29.11.21

Eric: G. ..

13

M

Schoolboy

23 Belgrave-street, Bed Hill

C.P.H.

24.11.21

28.11.21

P

5.12.21

Employed on Saturdays at Head’s Grocery Store (see Case 10), at which an infected rat was found on 28.10.21. Two sisters of thi=* patient were employed at Bickford and Sons, Little Boma-street, where infected rodents were found on 24th, 26th. and 28th October, 1921.

Remarks.

Table 51—Metropolitan Area oe Brisbane—continued. Human Cases of Plaguecontinued.

No.

Date

reported.

Name.

Age.

Sex.

Occupation,

Address.

By whom reported.

Date of Onset.

Dare Isolated.

Susp.

or

Pos.

Dis

charged

cured.

Date of Death.

35

2.12.21

C.F.

70

F

28 John - street,

C.P.H.

30.11.21

1.12.21

P

3.12.21

Valley

30

5.12.21

W .M. ..

32

M

Gloucester - street,

C.P.H.

4.12.21

5.12.21

P

12.1.22

, ,

South Brisbane

and

and

19.1.22

23.1.22

37

0.12.21

M.E.S. ..

20

F

“ Norbury,” Race-

C.P.H.

5.12.21

6.12.21

P

17.1.22

course-road, Ascot

38

12.12.21

W.McD.

12

M

Schoolboy

579 Boundary-street,

C.P.H.

8.12.21

11.12.21

P

13.12.21

Spring Hill

39

12.12.21

K.C. ...

•).>

F

Laundress

Bond-street, West

C.P.H.

9.12.21