Epidemiological study of hepatitis E virus infection in the general population of Okinawa, Kyushu, Japan.

ABSTRACT

BACKGROUND AND AIM: The aim of this study was to investigate the prevalence of hepatitis E virus (HEV) infection in the general population of Japan by determining presence of the antibody to HEV (anti-HEV). METHODS: The prevalence of HEV infection was determined by positivity of serum antibody to HEV (anti-HEV). RESULTS: On retrospective analysis, a significant decrease in anti-HEV prevalence was found in Okinawa healthy residents from 1995 (15.8%) to 2005 (5.5%) (P < 0.0001). In 2005, the anti-HEV prevalence was significantly higher in Okinawa wild boar hunters (25.3%) than in the residents (male 7.7% and female 4.1%) (P < 0.0001). A significant difference was found in the history of consumption of undercooked or raw boar meat between anti-HEV positive and negative hunters (100% vs 64.3%) (P = 0.0018). CONCLUSIONS: In conclusion, the anti-HEV prevalence has decreased in the residents of this area, but HEV infection has continued at a high rate in the hunters through the custom of eating undercooked or raw boar meat.