Recent trends in hepatitis B virus infection in the general Korean population

BACKGROUND/AIMS: Hepatitis B virus (HBV) is the major cause of chronic liver disease in Korea, but viral prevalence has decreased because of hepatitis B vaccination programs. In this study, we investigated longitudinal changes in HBV in fection in the general Korean population. METHODS: HBV surface antigen (hepatitis B surface antigen, HBsAg) seropositivity was assessed from the Korea National Health and Nutrition Examination Survey (I to V). In total, 50,140 subjects were tested for serum HBsAg positivity over a period of 12 years (1998 to 2010). RESULTS: The prevalence of HBsAg seropositivity decreased over the study period. The rates of HBsAg carriers were 4.61% in 1998, 4.60% in 2001, 3.69% in 2005, 3.01% in 2008, and 2.98% in 2010 (p < 0.0001). The reduction in HBV infection rates was more prominent in younger age groups. Among teenagers (10 to 19 years), the percentage of HBsAg carriers decreased from 2.2% in 1998 to 0.12% in 2010 (p < 0.0001). Among those aged 10 to 39 years, the percentage of HBV infection decreased from 4.72% in 1998 to 2.29% in 2010 (p < 0.0001). However, no decreasing trend in HBsAg positivity was observed among those aged 50 or older (p > 0.05). Neither gender nor socioeconomic status were associated with the decreased prevalence of HBsAg carriers. CONCLUSIONS: HBV infection has decreased in the Korean population since the advent of vaccination programs. However, the decrease is limited to the younger population, and viral persistence remains in the middle-aged and older population.