ENG-1958 — Page 162

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HONG KONG ANNUAL REPORT

syphilis and leprosy, quite apart from the routine work of the diagnosis and treatment of skin ailments. Over 50,000 attendances were recorded at these skin clinics in 1958 at which biopsies, fungus culture and patch testing for allergy, and antibiotic sensitivity tests are available.

Malaria. The number of cases notified in 1958 was 659. One death was recorded; this occurred in an elderly patient suffering from cancer who was accidentally infected during the course of repeated blood transfusions. Ninety five per cent of all notified cases originated in unprotected areas of the New Territories; the Sai Kung peninsula accounted for 85% of the total. This region has some 38 scattered villages and a large population living in junks and sampans amongst whom the great majority of cases occurred. }

Benign tertian parasites were found to be the predominant infection in over 90% of cases; some 50% were malignant tertian; and 3% were quartan.

The method of control continues to be mainly based on anti- larval measures. Areas at present under active and permanent control measures consist of the populated portion of the whole of Hong Kong Island and Kowloon; this corresponds to the urban areas of the Colony in which the main part of the population is concentrated. In addition, in the New Territories, the town area of Cheung Chau Island, Rennie's Mill Camp and Chi Ma Wan Prison are similarly protected. Ground control work at the Tai Lam Chung Reservoir site was terminated towards the end of September 1958, on completion of construction of the dam. Work in the Castle Peak area was likewise discontinued in October when the screening of the new Mental Hospital buildings was undertaken as a protective measure not only against mosquitoes but also against flies and other winged insect pests.

At Hay Ling Chau the anti-malaria work is undertaken by the Leprosarium staff, while the necessary insecticides are supplied by the Government Malaria Bureau.

Since 1957 anti-malaria oil has been employed as the main larvicide. In view of insecticide resistance problems, the use of Gammexane Dispersible Powder (P520) has now been confined