An epidemic of type B viral hepatitis: its course and outcome.

Between June and August, 1977 there was a small epidemic of type B viral hepatitis in a market town in South-East England during which 4 people developed acute hepatitis. Their close friends and contacts were all negative for hepatitis B surface antigen (HBsAg) at this time. One year later, in July 1978, 3 of the original 4 patients were available for follow-up. All were HBsAg negative but hepatitis B surface antibody (anti-HBs) and hepatitis B core antibody (anti-HBc) positive. Two had disturbed liver function tests and chronic persistent hepatitis on liver biopsy. Also at this time 2 of the original contacts were found to show evidence, from the serum markers, of previous infection by the type B virus. Both had abnormal liver function tests and showed chronic persistent or chronic active hepatitis on liver biopsy. A further subject was identified who had had an overt hepatitis 1 year previously and who also showed evidence of continuing liver disease. The origin of the epidemic and its spread through the group were identified. The varying modes of transmission, and the variation in clinical picture and sequelae are discussed. The importance of anti-HBc as a marker of hepatitis B virus infection is emphasised.