Survey of hepatitis B virus infection status after 35 years of universal vaccination implementation in Taiwan

Background and aims Hepatitis B virus (HBV) vaccination programs in Taiwan are one of the earliest programs in the world and have largely reduced the prevalence of HBV infection. We aimed to demonstrate the vaccination efficacy after 35 years and identify gaps toward HBV elimination. Methods A total of 4717 individuals aged 1–60 years were recruited from four administrative regions based on the proportion of population distribution. Serum levels of hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti‐HBs), and hepatitis B core antibody (anti‐HBc) levels were assessed. HBV viral load, genotypes and HBsAg ‘ɑ’ determinant variants were evaluated if indicated. Results After 35 years of vaccination, the overall seropositivity rates for HBsAg and anti‐HBc in Taiwan were 4.05% and 21.3%, respectively. The vaccinated birth cohorts exhibited significantly lower seropositivity rates for both markers compared to the unvaccinated birth cohorts (HBsAg: 0.64% vs. 9.78%; anti‐HBc: 2.1% vs. 53.55%, respectively; p