OBSERVATIONS ON THE SPREAD OF CHOLERA IN HONG KONG, 1961-1963.

Cholera, which had been spreading throughout the south-west Pacific in 1961, broke out in Hong Kong in August of that year. The outbreak lasted about six weeks, and recurred in 1962 and 1963; but whereas the 1961 outbreak resembled classical cholera, in the succeeding years the pattern changed. The disease, though still severe, was sporadic and this made it possible to study the epidemiology of the outbreak in some detail. Transmission bore little relation to water or food. A technique of nightsoil sampling was devised, and the results obtained in 1963 indicated the presence of a large number of symptomless excretors of cholera vibrios among the population. The authors suggest that this would make the hypothesis of person-to-person spread a more reasonable proposition than transmission simply from case to case.