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rate per thousand from malaria is given as .56. In certain areas where the majority of the population reside, extensive drainage has been largely carried ou, and in consequence there are, as a rule, no facilities for breeding of Anophelines but where such exist, as in suburban and rural areas on the Island and mainland, the occurrence of malaria can be reckoned on where the Anophe- line carriers flourish as is borne out by the investigations made in the past.
In Table I figures are given regarding hospi al admissions, supplied by the fovernment Civil, Kowloon, Victoria, Victoria Gaol, Lai Chi Kok Gaol, Tung Wah, Tung Wah Eastern, Kwong Wah. Matilda. Alice Memorial, War Memorial, and the Yeung Wo Hospitals and their relations to admissions for malaria. The malaria admissions are also arranged according to quarters of the year and to method of diagnosis. As malaria is not a notifiable disease, rates cannot be given for the general popula- tion. The linical diagnosis of malaria is not a satisfactory one,
In Table II statistics of cases treated, supplied by the following Dispensaries are shown: Tai Po, Un Long, Western Public, Kowloon City, Sham Shui Po, Shaukiwan, Aberdeen, Central. Fastern, Yaumati, and Hung Hom,
Table III deals with hospi al admissions of Government servants (excluding coolies) in relation to admissions for malaria.
Table IV is a similar table for the Police including Water Police. Certain stations are situa ed in areas where malaria is not likely to be contracted, others in rural areas where night patrol work adds o the risk of infection.
Table XIII gives the results of examinations of blood fibus for malaria made from prisoners admitted to Victoria Gaol, arranged in districts according to addresses supplied. The para- sites are no classified, as in the great majority of positive find- ings. the diagnosis could only be made from the thick films supplied, and could not be established from the thin films owing to the scantiness of the infec ions. The films were obtained through the cooperation of the M.O. Gaol and his staff, and were stained in the Laboratory of he Bureau,
Table XIV gives details as to results of examination of blood for malarial parasites in connection with investigations made in the corresponding localities.
Twenty-six children were examined on the Island, none had enlarged spleens. On the mainland two hundred and seventy eight were inspected, eighteen had enlarged spleens, or 6.47 per
Table XV gives details and localities.
cent.
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Records obtained from the R.A.M.C. authorities regarding incidence of malarial infection amongst the troops, British and Indian, are as follows, (relapses not being taken into account) :— British troops, number of cases of malaria contracted during the year was 45, of which one occurred in 1st. Quarter, 3 in 2nd. Quarter, 16 in 3rd. Quarter, 25 in 4th. Quarter. Calculated on an average strength of 2,271, the admission rate for the year was 19.82 per 1,000. Amongst the Indian troops there were 24 infections, of which there was none in 1st. Quarter, 6 in 2nd. Quarter, 10 in 3rd. Quar.er, 8 in 4th. Quarter. These work out for the year as 18.00 per 1.000 on an average strength of 1,389.
Dengue.
Ten cases were admitted to the Government Hospitals in 1932. No specimens of Aedes argenteus were met with, but Aedes albopictus were frequently encountered. This mosquito bas been experimentally infected with dengue in other countries.
Filaria.
Two cases of disease due to filarial infection were reported from the Government Hospitals during the year. Whilst dis. secting an Anopheles minimus obtained from the Wong Chuk Hang Village area for malarial infection, a filaria worm was ob- served emerging from the head after it had been pulled off. On the thorax being teased out, more worms were observed. After- wards other A. minimus were found infected from this area. In consequence thick blood films were obtained from 106 residents In the locality; these were taken at 10 p.m. in the moath of June. Microfilaria were found in 13 of these or 12.26 per cent, and malaria parasites in 6 or 4.62 per cent. One person harboured both kinds of parasites. Practically all stages of development were met with in A. minimus, the earliest being a worm which having penetrated the midgut had become entangled in the tracheal tubes on the exterior. Sausage shaped forms were found in the thorax, also long motile forms, and long motile forms in the head. No worms were met with in the proboscis although frequently looked for, but these mosquitoes are usually only kept until midgut appears free from blood.
Complete developmen: of the alimentary canal, and the narrowing of the worm beyond the anus, has been observed in some of the specimens. Seven A. minimus have on dissection been found infected with malarial and filarial parasites. On thirteen occasions the worms have been found in the abdominal
cavity of the insect. C. fatigans and A. jeyporiensis have also been found infected. In the case of the C. fatigans, the worms were all of the long motile variety, they were met with in thorax and head but not in proboscis. No long forms were found in A. jeyporiensis. Results of dissections for filaria are shown in Table XII. Six thick films from one thousand five hundred and thirty
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