PUBLIC HEALTH AND URBAN SERVICES
information from the Chinese mainland, all Chinese ports east of Canton were regarded as being infected with smallpox. A considerable number of ships were inspected and fumigated with sulphur and cyanide and a survey of small craft in the waters of the Colony showed that a certain amount of mosquito breeding was taking place in junks. Aedes aegypti was the pre- dominant species and was found to be breeding almost exclusively in drinking-water storage receptables of cargo junks employed as lighters. As this mosquito is responsible for the transmission of yellow fever, it is most important that it should be kept under control. The absence of Aedes aegypti breeding ashore pointed to the introduction of this species by vessels from outports. Control measures were directed mainly to breaking the breeding cycle of the Aedes by the frequent cleansing of drinking water storage receptacles. These measures appear to have been successful as only 26 cases of breeding were discovered during the year.
The Malaria Bureau. The staff of the Malaria. Bureau which is responsible for the control of malaria in Hong Kong consists of a malariologist, malaria inspectors, and daily paid overseers and labourers. The population at risk in the area controlled by the department is about 2 millions including about 25,000 Europeans. The cost of the anti-malarial work which is by larval control methods works out at 20 cents per head of the population per annum. This also includes the cost of control of nuisance mosquitoes. In addition to the protection of the civilian population, consultative work is done and many surveys are carried out on behalf of the Royal Navy, Army and Royal Air Force in the New Territories and outlying islands.
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