ENG-1957 — Page 174

PUBLIC HEALTH

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The Colony experienced a large scale outbreak of a type of influenza, popularly christened 'Asian flu', in the late spring. The source of the attack was uncertain, but the disease had been prevalent in Japan during the preceding winter months and had later spread to China. In Hong Kong the incidence showed a sudden rise in the second week in April and reached epidemic proportions by the end of the month; the total number affected was not accurately ascer- tainable since the disease was not notifiable, but a reason- able estimate indicates that about 10% of the population suffered from the condition; this figure corresponds to approximately 270,000 persons. There was some curtailment of public transport services and of industrial output, but schools were not closed.

Specific preventive measures of any effective value are not possible in this type of outbreak and no vaccine was available at the time.

A number of extra Government Medical out-patient clinics were opened, and night sessions from 6 p.m. to midnight were held in existing clinics in order to deal with the abnormal numbers needing treatment. These clinics were maintained for two weeks, including the Easter Holiday week-end, during the height of the epidemic.

The clinical course of the 'disease was mild and very few complications were noted. A total of 40 deaths was ascribed to influenza during the three months period March to May, over half these deaths occurring in persons over 60 years of age. The outbreak rapidly declined at the beginning of May and no secondary wave of cases has so far occurred.

The virus responsible was identified in several Far East areas as a new type, now known as type A/Asian/57, which has since spread to most other parts of the world and caused appreciable epidemics.

Information of a recurrence of cases in Japan was received in October and caused some concern lest the Colony be