Seroprevalence of HBV and HCV in female sex workers from four cities in the state of Pará, northern Brazil.

Female sex workers (FSWs) represent a high vulnerability group for the acquisition of sexual and parenteral infections such as hepatitis B virus (HBV) and hepatitis C virus (HCV) infections. The present study aimed to determine the prevalence of serological markers and risk factors associated with exposure to HBV and HCV among FSWs in the state of Pará, Brazil. A cross-sectional study using principles of the time location sampling (TLS) method was conducted in four cities (Belém, Bragança, Barcarena, and Augusto Corrêa) of the state of Pará, from 2005 to 2006. In total, 365 FSWs were interviewed using a standardized questionnaire. Blood samples were collected and tested for serological markers of exposure to HBV and HCV using an enzyme immunoassay. The overall prevalence of exposure to HBV and HCV was 36.7% and 7.7%, respectively. The prevalence of surface antigen of HBV was 3.0%. The prevalence of anti-HBc and anti-HBc+ anti-HBs antibodies were 6.3% and 27.4%. Very few (4.7%) FSWs had vaccine immunity against HBV (anti-HBs antibodies only). The prevalence of anti-HCV antibodies was 7.7%. Low monthly income, drug usage, and unprotected sex were some of the social characteristics associated with exposure to the viruses using different analysis. The seroprevalence of HBV and HCV infections among FSWs in four cities of the state of Pará is high when compared to the general population of Brazil, but similar to those found in FSWs in other nondeveloped countries. The prevalence of HBV was higher in Belém, while the prevalence of HCV was higher in the other three cities, highlighting the importance of establishing control and prevention programs to reduce the risk of acquiring these viruses in Pará.