ENG-1958 — Page 157

PUBLIC HEALTH

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134 deaths, giving a case mortality rate of 8.6% as compared with 10.4% in 1957.

A sudden sharp increase in the reported incidence of polio- myelitis occurred in the summer months, from May to August, during which time 244 out of the year's total of 262 cases were notified. The pattern of incidence followed the experience of previous years on a somewhat large scale. While poliomyelitis of the infantile type has occurred sporadically in this area for many years, the distribution of cases now occurring may be indicative of a shift towards the more epidemic form of the disease.

There has been observed in many of the less developed parts of the world an almost constant inverse ratio between infant mortality rates and poliomyelitis case rates, with a corresponding change in the pattern of the disease from a sporadic disease of infants to an epidemic disease of more severe form with a tendency to include older children and adults. This transition also appears to be linked to raised levels of hygiene and environmental sanita- tion which result in postponement of the age when natural mild infection and consequent immunity might be acquired. This gives rise to a susceptible community of older persons in whom the disease is likely to be more dangerous. It is possible that this situation may be expected in Hong Kong where the infant mortality rate has been halved during the last decade and improved methods of sanitation continually extended.

Advice on the value and expediency of a mass anti-poliomyelitis vaccination programme for the general public, using a Salk type vaccine, was sought from the World Health Organization Regional Adviser on Poliomyelitis in Singapore, He later visited the Colony to assess the local situation and to advise further on the possible use, at a later stage, of an oral attenuated live vaccine.

Ophthalmia neonatorum, an eye infection of new-born infants, was made a notifiable disease for the first time, the objective being the institution of early treatment of the disease, which is a potent cause of blindness in childhood. Since June 1958, 105 cases have been reported.

Notifications of tuberculosis showed a welcome decrease. The mortality rate for this disease fell for the first time below 100 deaths per 100,000 persons to 83 deaths per 100,000.