Viral hepatitis in the eastern Bay of Plenty.

Three hundred and fifty-three patients diagnosed as viral hepatitis and 2100 obstetric patients were tested for hepatitis B surface antigen (HBsAg). Forty-three percent of the acute cases were HBsAg positive. The age distribution of hepatitis B closely matched that for hepatitis unspecified and the highest incidence of both was in the age-group 6-10 years. Two-thirds of all cases of viral hepatitis in Maoris were children less than 15 years old, compared with one-third for Europeans. Infants of obstetric patients thought to be carriers of HBsAg were tested for this antigen five months or more after birth. Seven of 30 infants were carriers of HBsAg, all of high titre, as were their mothers.