Diphtheria
28. Only 25 cases of the disease were notified during the year, an even lower figure than the 43 cases recorded in the previous year. As a result of annual immunization drives since 1959, the disease has shown a continuous and steady decline, falling from 2.087 cases in 1959 to 25 cases in 1971. The disease affects largely children, and 76 per cent of the year's cases were under 10. Two deaths were recorded, giving a case fatality rate of eight per cent. Corynebacterium diphtheria mitis remained the predominant organism isolated in clinical cases.
Enteric Fever
29. The number of cases notified was $15, an increase of 77 cases over the preceding year. The disease was generally mild, and the case fatality rate was less than two per cent Transmission of infection was Frequently associated with neglect in personal and food hygiene. As elsewhere in the world, the peak incidence occurred among children of school age and young adolescents. Free inoculation was offered, and the usual preventive measures enforced, with special attention to environ- mental and food hygiene, and the control of food premises.
Malaria
30. The incidence of malaria during recent years has fallen to a very low level, and again no fresh case of the disease due to natural transmission was reported. Of the nine cases recorded during the year, seven were imported, one was recurrent, and one was due to blood transfusion.
Measles
31. A total of 591 notifications of the disease was received during the year. As shown in Figure 4, the incidence of measles in Hong Kong bas in previous years tended to fall into a distinct biennial pattern, with exacerbation of the disease every alternate winter and spring Since December 1967, measles vaccine has been available regularly at all government maternal and child health centres, and during campaign periods, the vaccine bas also been made available through mobile teams to children living in resettlement and bousing estales, tenement buildings, and other crowded areas. Since the last epidemic in 1966-67, the disease incidence and its mortality have remained low. These results were due. at least in part, to immunization campaigns which are now on a year- round basis, and continuing health education efforts to encourage parents to seck early medical advice.
599, or HofricKINLE
Poliomyelitis
FIGURE 4
MONTHLY MEASLES NOTIFICATIONS, 1961 - MAY 1972
THA
K
الساد
32. Only two cases of poliomyelitis were reported during the year. This showed a significant reduction when compared with 27 cases in 1970, and was the lowest recorded since the introduction of the poliomyelitis vaccination campaign in 1963. Both cases were of the type 3 poliovirus infection, confirmed by laboratory investigation. The programme of vaccination consisted of giving one dose of type 1 polio-vaccine, soon after birth, followed by two doses of balanced trivalent vaccine at three and five months. Beginning in October 1971, a booster dose of the vaccine was introduced at the age of about 18 months.
33. Approximately 74 per cent of infants received one dose of type I polio-vaccine soon after birth, and 72 per cent of infants received two doses of the trivalent vaccine at maternal and child health centres. A general immunization campaign is mounted annually in January and March.
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