Impact of universal infant hepatitis B vaccination in the US-affiliated Pacific Islands, 1985-2015.

The US-affiliated Pacific Island countries (USAPI) is an endemic region for hepatitis B virus (HBV) infection. Universal infant hepatitis B vaccination was introduced in the USAPI in the mid-1980s to mitigate the HBV burden. We assessed the impact of universal infant vaccination on the HBV infection prevalence over time among children born in the 1980s, 1990s, and 2000s in the USAPI. Demographic and serologic data from serial sero-surveys conducted between 1985 and 2015 were obtained. Descriptive statistics and analysis of variance were performed. From data obtained from 4827 children (2-11years), HBV prevalence decreased markedly: 8.4% in the 1980s; 2.5% in the 1990s; and 0.2% in the 2000s (P<0.0001) as vaccination coverage increased: 76.4% in the 1980s; 87.3% in the 1990s; and 97.5% in the 2000s (P<0.0001). These findings underscore the protective effect of universal infant hepatitis B vaccination over time on the HBV burden in an HBV endemic region.