M 19
28. Plague.—Four cases of bubonic plague occurred with two deaths. These are the first cases of either human or rat plague which have been reported since September 1923. All came from the Eastern District of the City of Victoria. The first two cases were reported on May 4th. They both occurred on the same floor of a good type tenement house which was used for residential purposes only. The third case was reported on June 23rd and the fourth on July 23rd. No dead rats were found and no infected rats were reported from this or any part of the Colony. House-to-house cleansing was carried out.
29. Rat Flea Survey.—With the object of starting a rat flea survey, arrangements were concluded with the Head of the Sanitary Department for a number of wire cage traps to be set in various parts of the city, so that rats caught should remain alive until dealt with by the investigator. Experience had shown that rats found on bird-lime traps (the kind usually set) were dead when collected and free from fleas.
30. The collection and differentiation of the fleas was until June under the supervision of Dr. T. W. Ware, after which time Dr. H. A. Fawcett carried on the work. The total rats examined was 259 and the number of fleas found was 1,330. The following Table shows details of the results obtained:
Species No. found Average per rat Xenopsylla Cheopis 1,249 4.82 Leptopsylla Musculi 59 0.23 Ctenocephalus 18 0.07 Pulex 4 0.01The number of rats examined is too small for definite conclusions to be drawn, but it is hoped that a continuation of the survey may throw light on the epidemiology of plague.
31. The absence of Plague from Hong Kong for so many years may be due to the sanitary measures which have been and are being taken, but it has apparently also disappeared from Canton and South China generally, where similar measures have not been in use.
32. Enteric.—The number of cases reported was 240. All the cases were sporadic and, as is usual in such cases, the source of infection could not be traced. There are, of course, a number of possible sources of infection included among which are raw vegetables grown by the Chinese method, foods and drinks contaminated by infected water, adulterated milk, flies, etc., etc. There is no evidence that any case contracted this disease through the public water supply.
33. Helminthic Diseases.—(c) The Hospital returns show 72 cases of ankylostomiasis, 5 cases of cestodes, and 91 cases of ascaris infection.