The spread of hepatitis A virus in connection with hepatitis cases in children's communities.

In order to investigate the characteristics of hepatitis A virus excretion, 372 children in semi-closed day-care centres were examined at the time of the seasonal increase in hepatitis incidence. Enzyme immunoassay and immune electron microscopy were used to detect virus in faeces. Ten communities were surveyed and, for the purposes of this paper, were divided into four groups on the basis of the observed pattern of virus excretion.