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HONG KONG ANNUAL REPORT
plans and supervises immunization campaigns for the prevention of smallpox, typhoid fever, diphtheria and other diseases.
Air traffic was particularly heavy and 45,615 passengers and crew members from infected ports were inspected by Port Health staff during the year; 613 of these were subjected to quarantine measures, mostly by surveillance, on arriving in the Colony.
All persons entering the Colony by the land frontier at Lo Wu were vaccinated against smallpox if not in possession of valid certificates of vaccination or a re-entry permit issued by the Hong Kong Police.
Medical inspections of unberthed passengers travelling as emi- grants on ships continued to be carried out; a total of 7,154 of these inspections was made in the year on board sixty six ships.
International deratting certificates were issued to seventy two vessels after fumigation with either hydrogen cyanide or sulphur dioxide, and deratting exemption certificates were granted to 130 ships after inspection. The dock area and airport are included in the rodent control scheme for the Colony and returns of rodents destroyed and bacteriological examinations carried out for P. pestis were submitted weekly to the W.H.O. Epidemiological Intelligence Station, Singapore.
Mosquito control measures were continued throughout the year. The port and airport were kept free from Aedes aegypti in its larval and adult stages as required by Article 20 of the Inter- national Sanitary Regulations.
A routine check was maintained on the purity of drinking water supplies to ships by bacteriological examination of weekly samples from water boats and dock hydrants; of 521 samples taken remedial action was required in eighty cases where the results were below standard.
Maternal and Child Health Services. These services offer, on an ever-increasing scale, free maternal and child care on an out- patient basis. The services operate from seven full-time centres in the urban areas and hold sessions in regional and outlying dispensaries. Antenatal, post-natal, infant welfare and 'toddler' clinics are conducted regularly. Antenatal clinics were held on 1,831 occasions in the year and attendances showed a 12% rise over the 1957 figures, although post-natal visits showed little