Prison population 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 the circulating genotypes/subtypes.
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 after and included 1,656 individuals. Participants underwent an interview and blood collection for the detection of HBV serological markers and HBV-DNA phylogenetic analysis.
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 male, 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 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%).
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.

Copyright © 2020. Published by Elsevier Ltd.