Impact of universal preadolescent vaccination against hepatitis B on antenatal seroprevalence of hepatitis B markers in British Columbia women.

Countries with a low risk of hepatitis B (HB) lack data on the effectiveness of universal HB vaccination programs for children. British Columbia began a program in 1992, offering HB vaccination to 11 year olds. We conducted an anonymous, unlinked serologic survey 7 years later, analyzing a random sample of specimens (n = 1215) from women aged 15-44 years who had undergone antenatal rubella testing. Among those aged 15-19 years inclusive there was no evidence of chronic HB (HB surface antigen), the proportion with evidence of acute HB (anti-HB core antibody) was only 0.6% (compared with 6.5% for the entire sample), and evidence of protective immunity was strong: the prevalence of anti-HB surface antibody (anti-HBs) was 79.1% (compared with 41.4% for the entire sample) and the geometric mean titre was 34.9 IU/mL (compared with 0.6-0.8 IU/mL for the older groups [p < 0.001]).