Poliomyelitis
58.
Three cases of poliomyelitis vere reported during the year as compared with four in 1972. Two of the three cases were of the type 3 polio- virus 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.
59.
Approximately 94 per cent of infants received one dose of type 1 polio-vaccine soon after birth, and 77 per cent of infants received two doses of the trivalent vaccine at maternal and child health centres. The annual general immunization campaign against poliomyelitis was held in January and March.
60.
Virological investigation of the disease was maintained throughout the year. A poliomyelitis faecal survey among normal children aged under five was carried out in July-August. The result showed that the excretor rate of vaccine' types of poliovirus was 2.60 per cent, among a total of 461 children included in the survey. The 'wild' type of poliovirus (type 3) was detected in four children giving an excretor rate of 0.87 per cent. The findings of the survey indicated the continuing existence of 'wild' poliovirus type 3 in the community, but did not demonstrate the existence of type 2 poliovirus.
Influenza
61.
The surveillance programme for influenza was continued on a year-round basis. Several general out-patient clinics have been designated as influenza surveillance centres, and these reported regularly the number of
The government virus unit continued to
influenza-like illnesses seen.
function as a World Health Organization National Influenza Centre during the year, and virological investigations of throat swabbings and throat washings were carried out routinely on samples taken from influenza-like cases. Deaths from influenza, pneumonia and bronchitis were recorded regularly as part of the programmes of epidemiological surveillance of the disease.
62.
The disease occurred sporadically between Jamiary to October. The most prevalent strains of influenza A virus occurring were A/England/42/72 and A/Port Chalmers/1/73. Influenza virus B strain B/Hong Kong/5/72 and other para-influenza virus were also isolated during the year.
Tetanus
63.
This disease, although not notifiable, was recorded during the period under review with reasonable accuracy owing to the severity of the symptoms, requiring hospitalisation of clinical cases. In the past years, approximately half the cases reported were among the new-born whose births had not been attended by trained staff, and who had been exposed to various hazards from unsterile equipment and herb powders. In 1973, tetanus neonatorum was responsible for only 1.8 per cent of recorded cases, and infant mortality from such infection fell from 1.2 deaths per 1,000 in 1951 to 0.012 deaths in 1973.
Viral Hepatitis
64.
Notification of this disease remained voluntary.
A total
of 509 cases was notified in 1973. Most cases were among adolescents and adults, and a higher proportion was found among men. During the year, steps were taken to promote better and more complete reporting and investigation of the disease. Amendments to the Ordinance and Regulations to make this a notifiable disease are about to be introduced.
65.
Developments in other communicable discases showed little variation during 1973.
III. WORK OF THE HEALTH DIVISION
AREA HEALTH WORK
66.
Area health officers worked during the year to maintain satisfactory standards of environmental sanitation and food hygiene. they also carried out field investigations into the major communicable diseases, and helped to co-ordinate the activities of teams of inoculators participating in prophylactic immunisation campaigns.
Brut
67.
Four such campaigns were carried out. They were against poliomyelitis, measles, diphtheria and smallpox. Hong Kong has not had a case of smallpox since June 1952, and the latest drive against the disease, held in February 1974, was intended to remind the public of the need to preserve this record. Moreover, the sudden outbreak of smallpox in the spring of 1973 in Britain, focussed attention on vigilence, in view of Hong Kong's increasing importance as a crossroad in international travel in this part of the world.
68.
With the reorganization of the Urban Council during the year, the District Health staff were physically and functionally dissociated from the Urban Services Department. Having been spared from the routine environ- mental hygiene work, they can now devote their time on community health work.
69.
TUBERCULOSIS
The policy for the control of Tuberculosis continued during the year to be to protect, by vaccination with B.C.G., the new-born, who were particularly vulnerable to the fulminating forms of the disease, and primary School entrants and school leavers who could develop active disease later in life. For actual cases of the disease, it has been shown that in a large proportion of cases, out-patient therapy is at least as good as institutional treatment. In complete contrast to the past, there is now no waiting list for hospital admission for the treatment of tuberculosis. Institutional resources are reserved for those not responding to out-patient therapy, for acutely. ill cases, for those where the diagnosis is in doubt, and for those in need of surgical intervention. In line with this policy, there is a high degree of co-operation between the Government and voluntary agencies concerned with the problem particularly the Hong Kong Anti-Tuberculosis and Thoracic Diseases Association, the Haven of Hope Sanatorium, and the Tung Wah Group of hospitals.
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