Two decades of universal hepatitis B vaccination in taiwan: impact and implication for future strategies.

BACKGROUND & AIMS Following the world's first successful implementation of a universal hepatitis B virus (HBV) vaccination program for infants in Taiwan 20 years ago, we performed this study to evaluate the long-term protection afforded by HBV vaccination and to rationalize further prevention strategies. METHODS HBV seromarkers, including hepatitis B surface antigen (HBsAg) and antibodies to HBsAg (anti-HBs) and core antigen (anti-HBc), were studied in 18,779 subjects from neonates to adults below 30 years of age in 2004. The birth cohort effect was evaluated by comparing the results of the same birth cohorts at different ages among this survey and the previous 1984, 1989, 1994, and 1999 surveys. RESULTS The seropositive rates for HBsAg, anti-HBs, and anti-HBc were 1.2%, 50.5%, and 3.7%, respectively, in those born after the vaccination program (<20 years of age) in 2004. A positive maternal HBsAg status was found in 89% of the HBsAg seropositive subjects born after the vaccination program. The absence of an increase in HBsAg seropositive subjects at different ages in the same birth cohorts born after the vaccination program implied no increased risk of persistent HBV infection with aging. CONCLUSIONS Universal HBV vaccination provides long-term protection up to 20 years, and a universal booster is not indicated for the primary HBV vaccinees before adulthood. Maternal transmission is the primary reason for vaccine failure and is the challenge that needs to be addressed in future vaccination programs. This may include an appropriate hepatitis B immunoglobulin administration strategy for high-risk infants and involve efforts to minimize noncompliance.