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HEALTH
the special infectious disease unit of the Princess Margaret Hospital scheduled for completion in early 1974.
Malaria is reported only in certain rural areas of Hong Kong. Of the few cases recorded in recent years most were either imported or recurrent cases. Malaria pre- vention in the urban areas is based chiefly on anti-larval measures consisting of drain- ing and clearing streams, ditching and oiling. In the greater part of the New Territories, where the background is essentially rural, screening of buildings, use of mosquito nets and chemoprophylaxis constitute the main protection against malaria. All anti- mosquito measures for the prevention of malaria are carried out by the Pest Control Section of the Urban Services Department. Clinical aspects of malaria control such as malaria surveys and chemotherapy are the responsibility of the Medical and Health Department.
Diphtheria occurred mainly among children under 10 years
of age, predominantly within the 'pre-school' age-group. The annual inoculation drive which has been in progress since 1959 continued to give encouraging results, and from the number of cases recorded in recent years, the stage of eradicating the disease from the community appears almost to have been reached. There has been a steady decline in the number of cases notified annually; in 1972 only five cases were recorded compared with 25 cases in 1971 and 2,087 cases in 1959. The vaccine used in the campaign is a combined vaccine against both diphtheria and tetanus.
Poliomyelitis has been brought under control since the introduction of the poli- omyelitis vaccination programme in 1963. During the year only four cases were reported. The vaccine is offered free at government maternal and child health centres and a general immunisation campaign is mounted annually in January and March. Infants in hospitals and maternity homes are given one dose of type 1 polio-vaccine soon after birth. This is followed by two doses of balanced trivalent vaccine at three and five months and a booster dose at 18 months. Epidemiological surveillance of the disease was maintained throughout the year. This included virological investigation of laboratory specimens for polio-virus and the carrying out of a poliomyelitis faecal survey among normal children to find out the distribution of polio-virus in the community.
Measles is most prevalent among children under the age of five years and epi- demics are characteristically biennial. In Hong Kong during epidemics the disease is usually associated with high mortality due mainly to complicated bronchopneumonia encountered too late for treatment to be effective. Since December 1967 measles vaccine was included in the public health vaccination programme and the vaccine is now regularly available at government maternal and child health centres. Anti- measles campaigns are conducted throughout Hong Kong each year, and for the year under report the campaign was started in August, lasting about nine weeks. During the drive, measles vaccine was made available at all government dispensaries, clinics and health centres, as it is usually, and also in other inoculation posts set up in resettlement and low-cost housing estates, health offices and other areas. The disease incidence and its mortality have remained satisfactorily low in the last five years.