isolation and treatment of the sick, legislation to minimize infection of food, intensive house to house inspections, disinfection of infected dwellings and mass inoculation.
78. The outbreak continued on into 1938 and 'was aggravated by the steady stream of refugees into the Colony. Many more males than females were affected by the disease'. According to the official reports, there was a total of 2,227 cases resulting in 1,445 deaths. However, Wilkinson (1943) has recorded this outbreak in some detail and accord- ing to his paper, the outbreak lasted until 1940. There are reports that the disease thereafter appeared sporadically during the first twelve months of the Japanese occupation.
Cases Deaths
TABLE 4
CHOLERA IN HONG KONG (WILKINSON 1943)
1937
1938
1939 1940
1,690
547
TOE
647
1,082
363
448
331
79. In 1940, a carrier rate of 20%, was found amongst certain sec- tions of the community just before the annual outbreak which started in June of that year and which reached epidemic proportions in July and August, waning during September.
$0. During 1946, the first case of cholera was reported on the 8th January and was definitely established as an imported case from Canton, A further 6 cases were notified during March, of which four were im- ported; a further 29 were notified in April of which 25 were imported. Special anti-epidemic measures were established on the 1st April in the face of a steady monthly influx of an estimated 100,000 returning residents and refugees. Despite rigorous measures of environmental sanitation and mass inoculation with cholera vaccine, epidemic propor- tions were reached in June when, during the week ending the 15th June, 112 cases occurred. Altogether there were 281 cases during June with 137 deaths. The last case of cholera was reported on 26th September, 1946, and thereafter no further case of cholera was confirmed in Hong Kong until the 16th August, 1961.
TABLE S
CHOLERA IN HONG KOno 1946
Bodies Dumped
BR
Cuses Local Imported
Total
514
374
52
18
Deaths
139
Inoculations Estimated Performed Population 311,608 1,550,000
81. There are no records of the detailed bacteriological findings prior to 1961 now available but it was assumed that all these infections were due to cholera Asiatica, predominantly of the Ogawa group. Haemolysis tests were not applied in the past and all the epidemics recorded presented the clinical picture of classical cholera.
The 1961 Outbreak
82. The infections confirmed during the Hong Kong outbreak in 1961 were proved, with one exception, to be due to the El Tor type of the Ogawa group of vibrio cholerae; there was only one infection of the Inaba group. Therefore, the recent history of paracholera or 'enteritis choleriformis El Tor" in this region of Southeast Asia is of some interest.
83. Paracholera has occurred periodically in epidemic form in Indonesia over the past 25 years. Neighbouring countries had remained free of the infection until the middle of 1960 when El Tor cholera vibrios were isolated in Bangkok towards the end of an outbreak of cholera Asiatica. At this time the El Tor isolates were cultured from a few patients suffering from mild diarrhoeal conditions and from samples of food and water. In September, 1960, an epidemic of para- cholera El Tor occurred in Northeast Thailand.
84. Meantime, an epidemic which started on the Sth January, 1960 in Macassar spread throughout the whole of Indonesia, affecting Java in 1961. The infection appeared in Sarawak in July, 1961, and con- currently paracholera was occurring in the Kwangtung Province of the Chinese Peoples Republic. Macau reported its first confirmed case on the 14th August, 1961, and the first two cases were confirmed in Hong Kong on the 16th August. On the 22nd September, 1961, the first case in the Republic of the Philippines occurred in Manila; in January, 1962, North Borneo was, in turn, infected.
The Hong Kong Outbreak
85. During the first week in August, international press agencies carried reports of an epidemic of cholera occurring in the Kwangtung Province of China. At the same time, travellers entering Hong Kong by railway at Lo Wu presented anti-epidemic certificates of inoculation, against the four diseases', with TAB-cholera vaccine. There were stories of a cholera-like disease affecting many villages in the rural areas of the province and causing many deaths. On the 10th of August, Reuter reported cholera in Macau, but this was not confirmed by the Macau Health Authorities. However, in view of the strength of the
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