Hepatitis delta virus infection in different time periods in Japan.

To investigate the prevalence of hepatitis delta virus (HDV) infection in different time periods between 1973 and 1988, antibody to hepatitis delta antigen (anti-HD) was tested for in sera collected from 1088 cases with acute or chronic hepatitis B virus (HBV) infection treated at Kure National Hospital. Between 1979 and 1983, anti-HD was first detected in 16% (four of 25 cases) of patients with acute hepatitis B, in 6.8% (11 of 161 cases) of asymptomatic HBV carriers and 26% (51 of 196 cases) of those with chronic liver disease. Except for this time period anti-HD was hardly detected. These findings indicate that sporadic HDV infections existed in this area between 1979 and 1983.