CURRENT SEROEPIDEMIOLOGICAL STATUS OF HEPATITIS-A WITH A COMPARISON OF ANTIBODY-TITERS AFTER INFECTION AND VACCINATION

The overall prevalence of anti-hepatitis A virus antibodies was 49.6% in 385 inhabitants in Hondo City, Japan in 1991. An approximately 50% prevalence rate occurred between 40 and 49 years of age. The prevalence of anti-HAV antibodies was significantly lower in 1991 than in 1982 in the age groups 20 to 29 years and 30 to 39 years (p<0.01), suggesting there has been no significant HAV infection since 1982. In addition, anti-HAV antibody titers of sera from convalescent hepatitis A patients were compared with those from seropositive healthy subjects and from healthy subjects following administration of a lyophilized inactivated hepatitis A vaccine or immune serum globulin. Titers after vaccine administration were considerably higher than after immune serum globulin and, although lower than those obtained after natural infection, should be sufficient for protection against hepatitis A virus. (C) Journal of Hepatology.