Background: Prison populations are at high risk for hepatitis B virus (HBV) infection. The aim of this study was to assess the prevalence, incidence, HBV associated factors and circulating genotypes/subtypes.
Methods: A total of 3,368 prisoners from 12 closed prisons were randomly recruited for a cross-sectional study. In addition, a cohort study was conducted 12 months later and included 1,656 individuals. Participants underwent an interview and blood collection for the detection of HBV serological markers and HBV-DNA phylogenetic analysis.
Results: HBV exposure (anti-HBc+) was 9.8% (95% CI: 8.8-10.8); 11.2% were female and 9.6% were male. HBsAg+ was 0.6%. Only 31.4% of the participants had HBV vaccination-like profile (anti-HBs+ alone; 30.4% male vs. 36.8% female; p=0.004). Most individuals were susceptible to HBV (60.2% female vs. 52.2% male, p=0.001). HBV isolates were classified as genotypes A (45.4%), D (27.3%) and F (27.3%). In males, HBV exposure was associated with increased age. Male prisoners had more evidence of HCV/HBV co-infection (10.7%) than females (3.4%) and the frequency of Treponema pallidum infection among prisoners who had been exposed to HBV was higher in female prisoners when compared with male (39.7% vs. 19.1%). The incidence of HBV was 0.18/100 person-years (95% CI: 0.12%-0.25%).
Conclusions: Our results indicate a high prevalence of HBV exposure in prisoners. Despite the low incidence of this infection, the occurrence of new cases indicates the need to implement preventive measures.
【저자키워드】 Epidemiology, HBV infection, prisoners,