Perfil soroepidemiológico da hepatite B em localidades ribeirinhas do rio Madeira, em Porto Velho, Estado de Rondônia, Brasil

It was conducted an observational study in two villages in Porto Velho, Rondonia State, Brazil, in order to evaluate the seroepidemiological profile of hepatitis B virus (HBV) and the risk factors in its transmission. Six hundred sixty samples were analyzed by ELISA method for serological tests for HBV (anti-HBc total, anti-HBs and HBsAg). The results showed that 50.7% (335) of samples were positive for some kind of serological marker. HBsAg was positive in 12 (1.8%) samples, 11 (91.6%) were from male ones. Anti-HBc total was positive in 212 (32.1%) samples distributed in all groups, except for the range of 11 to 16 years old. Anti-HBs was positive in 239 (36.2%) samples with the highest prevalence in groups over 21 years old. This study showed that the analyzed locations have low endemicity for chronic HBV carriers, however, there was a high prevalence of infection. The percentage of susceptible individuals was 49.2% (325), the highest was in individuals between 6 to 15 years old. Aspects of transmission such as dental extractions, surgeries and sharing personal hygiene materials are possibly associated with HBV infection in the analyzed region. Furthermore, the low percentage of anti-HBs marker indicates an immunization coverage failure in the population of this study.