Malaria Incidence.
159. During 1951, a total of 526 cases of malaria with 35 deaths were notified, comprising 340 cases of benign tertian, 140 subtertian, 18 quartan and 28 clinical malaria. Of these cases, 44 were Europeans, the majority belonging to the armed forces. Almost invariably, the infection was contracted outside the larval controlled area.
Malaria surveys.
160. Adult anopheline mosquito catching was carried out during the year in different parts of the New Territories, which were not included in the larval control programme, namely Woo Li Hop, Tai Po, Fanling, Sek Kong, Ma On Shan and Tai Shui Hang. A total of 16802 mosquitoes were caught and 12432 examined. It is rather perplexing to note that from dissections made, no infective mosquito was encountered. Frequent larval surveys were carried out during the year.
161. Since July 1951, blood smears have been obtained from children in different parts of the New Territories. 858 smears were thus examined, with 37 positive for malaria infection, giving a parasite rate of 4,31%.
162. In a separate survey conducted in July and September, 5 out of 187 blood smears taken from Cheung Shu Tan Village, Kam Chin Village and Woo Li Hop Village were found infected.
163. The spleen index and parasite rate of the children at Tai Lam Chung Village were taken in February 1952 when anti- malarial measures had just commenced. Of the 36 children examined, 9 were found with palpable spleens (spleen rate 25%). 2 out of 48 blood smears taken were found positive with malaria infection.
164. A malaria survey was also undertaken at Hay Ling Island (Leprosarium) during the year,
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Other work,
165. In addition to the routine work, much consultative work was carried out with the Royal Navy, Army and Air Force, At Sek Kong, New Territories, where the Army has started a big building project, much time has been taken for preliminary surveys on the spot.
166. Advice was given on the abatement of the fly nuisance at the Dairy Farm, Pokfulam,
TUBERCULOSIS CONTROL
167. The relative importance of tuberculosis in the mor- tality statistics of the post war years has continued to grow at an alarming rate. For the year 1951 this disease accounted for more than 20% of deaths from all causes as compared with the figure of 14.6, 16 and 17.7 per cent recorded from the years 1948-50 respectively. The mortality rate has increased by 44% over the 1950 figure and is almost double the rate recorded in 1947. It must be pointed out however that the 1951 figures probably represent a more accurate picture of the true situation than any of the figures since 1945 as the common practice normally adopted by the chronic sick, of returning to their native village is not now easy in view of the present restrictions at the Chinese border. At the same time economic conditions have recently deteriorated with an increase in the cost of living and a definite rise in the number of persons not in employment. Over-crowding has been materially alleviated although there has been a fall of more than 11% in the estimated total population.
168. Tuberculosis notifications show an increase of 63% over the 1950 figure. Some part of this increase is undoubtedly due to several factors-an increase in the diagnostic facilities available to the general public by the opening of the new Tuber- culosis Clinic in Kowloon, an intensification of the search for
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