160. In order to avoid as far as possible the danger of enhancing development of resistance of anopheline species to insecticides, it has been considered advisable since the beginning of the year to discontinue DDT residual spraying in the villages on the perimeter of the larval-controlled areas.
161.
The total number of cases of malaria notified for the year 1966 was 496, compared with 431 in 1955. The Table in Appendix 4 gives details of the source of the notifications, whether from the protected areas or elsewhere, the type of infection, and whether the cases are new cases or relapses.
162. During the year, 4 deaths from malaria were recorded, as compared with 9 in the preceding year. Of the 4 deaths, the diagnosis in two cases was not confirmed by blood examina- tion.
163. In the New Territories malaria surveys were carried out during the year at San Wai (Shatin), Kam Tsin, Cheong Shu Tan, Wong Toi Shan, Leung Tin, Kei Lun Wai, Ho Chung, Wo Mei, Nam Wai, Kai Ham, and Pak Kong Au villages. During these surveys, spleen examinations of children up to ten years, were performed. Altogether, a total of 706 children presented themselves for spleen examination and 804 for blood examination. The spleen rates varied from 0% to 12.0% and the parasite rates from 0% to 11.5% among individual villages. 164. With the assistance of the Medical Officer of Health New Territories and the Government Pathologist, blood smears were taken for examination for malaria parasites from all infants under 1 year of age attending clinics or health centres. Results are detailed in Appendix 5.
165. From this Appendix it is seen that the degree of malaria endemicity varies in different parts of the New Terri- tories, the Sajkung area shows the highest infection rate with Tsuen Wan the next most affected. Infection is practically all of the Benign Tertian (Vivax) variety.
Leprosy.
166. The vast majority of patients with this disease con- tinued to be treated at out-patient clinics with the object of rendering them non-infective as quickly as possible by modern treatment. This is justified by the proved fact that the infec- tivity of leprosy is extremely low.
167. Two additional weekly clinics were commenced during the year, one at Cheung Chau and the other at Shamshuipo Public Dispensary. Total attendances at clinics were 25,789; cases attending for the first time numbered 751. The number of lepers under active treatment at the close of the year was 1.670. 165 cases were admitted to Hay Ling Chau Leprosarium compared with 98 the previous year and 28 in 1954. 280 cases were also treated in Stanley Prison.
168. Familial contacts of infectious cases were followed up, and 195 such contacts were examined during the year. B.C.G. vaccination continues to be given for child contacts.
169. For treatment "dapsone" orally or by injection (202 suspension in oil, or "Avlosulphon Soluble") remains the stand- ard method. An average case requires a total dosage of 180 millilitres of this drug before conversion to negative smears is achieved.
170. Rehabilitation of cured cases continues to be difficult: the process of re-acceptance into the general community is a slow one.
171
An unofficial settlement of leprosy patients squatting at Sandy Bay near Pokfulam was cleared in July 1956 to allow completion in that area of a new convalescent hospital for crip- pled children.
172.
Infectious cases were sent to Hay Ling Chau Lepro- sarium. Most of the non-infectious were accommodated in new multi-storied resettlement housing estates in Kowloon and the remainder, who were physically disabled, were cared for by the Social Welfare Office.
Social Hygiene.
173. The incidence of venereal diseases continued to show a satisfactory decline in 1956 as the following table covering the previous three years shows:
Year
Table 17
Total No New Patient
Total No. Attendance
Total No. new Syphilia Caven
1954
36,65%
223,031
6.825
1955
34,850
203,701
4,280
33,490
1300, 1468
3,711
1956
韓
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