Hepatitis B virus infection in homes for the aged.

A seroepidemiological study was carried out in three different institutions for the aged. Serological evidence of HBV infection and the HBsAg carrier rate were found to be significantly increased in all three institutions with respect to the control group (noninstitutionalized aged). Of the 24 HBsAg asymptomatic chronic carriers 62% were positive for HBeAg. Among 15 patients with acute viral hepatitis, none had a severe course and in three HBsAg was not cleared 4-18 months after transaminase levels became normal. During 12-18 months of followup, two asymptomatic seroconversions to HBsAg were observed. Although no single HBV transmission route was identified, the close cohabitation with this high number of HBsAg/HBeAg-positive asymptomatic subjects could lead to an increased risk of spread of HBV within such institutions. Failure to clear HBsAg and the mild, often subclinical, HBV infection observed in these subjects, may be due to immunological abnormalities present in the elderly.