Trends in the seroprevalence of hepatitis B surface antigen in the South Korean population

SummaryBackgroundTrends in hepatitis B virus (HBV) infection are important in evaluating the effectiveness of the recommended routine vaccination of infants and adolescents.MethodsThe prevalence of HBV infection was determined in a representative sample of the Korea National Health and Nutrition Examination Survey for 1998 (n = 9771) and 2009 (n = 8304). Participants aged ≥10 years were tested for the hepatitis B surface antigen (HBsAg).ResultsThe overall age-adjusted HBsAg seroprevalence was 4.6% (95% confidence interval (CI) 4.2–5.0%) in 1998 and 3.2% (95% CI 2.9–3.6%) in 2009, which represents a relative decrease of 30.4% between the two survey populations (p < 0.05). The prevalence of HBsAg decreased among persons 10–19 years of age (from 2.2% to 0.3%), 20–29 years of age (from 5.4% to 2.5%), 30–39 years of age (from 6.1% to 4.3%), 40–49 years of age (from 5.1% to 4.7%), and 50–59 years of age (from 5.3% to 3.7%). HBsAg seroprevalence did not decrease among persons ≥60 years of age (2.7% vs. 2.9%).ConclusionsThese data show a decline in HBsAg seroprevalence, primarily due to the dramatic decrease in adolescents and younger adults.