1. The incidence of infectious hepatitis calculated from official notifications fluctuated between 5·7 and 11·4 per 10,000 during the years 1949–57, while reports of the Workers' Sick Fund indicated a rate three to four times greater. The highest rates were between the ages 1 and 9, two-thirds of the cases being under 10. Mortality was very low.2. Highest attack rates were seen under conditions of crowding, i.e. in agricultural schools, communal settlements and new immigrant towns. This fact, together with the winter peak of incidence, suggests a contact-respiratory form of spread.3. Immigrants, regardless of country, showed particular susceptibility during their first year or two in Israel. In the long run there was no difference in attack rate between immigrants from Western and from Middle Eastern countries, in spite of the known endemicity of the disease in the Middle East. In communities such as those from Yemen and North Africa, with large families and with, on the whole, a lower economic status, the mean age at onset was significantly younger. Among the non-Jewish population, the incidence was lower than expected due partly to under-reporting and partly, perhaps, to a mild form of the disease in the very young.
The epidemiology of infectious hepatitis in Israel