Study on the control of hepatitis B virus infection in an institution for the mentally retarded.

This study is a longitudinal epidemiologic survey (January 1980--December 1982) of hepatitis B virus (HBV) markers in an institution for subnormal people (62 patients--25 mentally retarded, 15 suffering from epilepsy, 15 from Down's syndrome, 7 from other diseases--and 23 nuns), in order to assess the prevalence and incidence of hepatitis B and the annual rate of seroconversion for HBV markers and to verify the efficacy of hygienic and prophylactic measures, that we adopted. Our data confirmed the efficacy of these measures, showing a significant decrease of HBsAg positive subjects and a parallel significant positivization of HBsAb positive subjects.