Seroprevalence of hepatitis B virus infection and associated risk factors among prison inmates in Mato Grosso do Sul, Brazil

The aim of this study was to estimate the prevalence of hepatitis B virus (HBV) serological markers and risk factors for this infection in prison inmates in Campo Grande, MS, Brazil. A total of 408 individuals were interviewed on socio-demographic characteristics, risk factors and HBV vaccination by means of a standardized questionnaire. Blood samples were collected from all participants and serological markers for HBV were detected by enzyme-linked immunosorbent assay. Hepatitis B surface antigen (HBsAg) and/or antibodies against hepatitis B core antigen (anti-HBc) positive samples were tested for HBV DNA by polymerase chain reaction. The overall prevalence of HBV infection was 17.9% (95% CI: 14.4-22.0). The HBsAg carrier rate was 0.5%, 56 individuals (13.7%) had been infected and developed natural immunity, and 15 (3.7%) were positive for anti-HBc only. An occult HBV infection rate of 0% was found among anti-HBc-positive individuals. Multivariate analysis of risk factors showed that age > 35 years, low schooling level, drug use and homosexual behavior are significantly associated with HBV infection. These findings confirm that inmates are at high risk for hepatitis B infection and indicate that preventive measures such as vaccination and education programs are recommended to control HBV infection in this population.