Hepatitis B Vaccination Coverage and Prevalence of Hepatitis B Surface Antigen Among Children in French Polynesia, 2014

Abstract

French Polynesia is considered to be moderately endemic for chronic hepatitis B virus infection, with an estimated 3% of the population having hepatitis B surface antigen (HBsAg). From 1990 to 1992, a 3-dose hepatitis B vaccination series was introduced into the routine infant immunization schedule in French Polynesia, including a birth dose (BD). In 2014, a nationally representative 2-stage cluster survey was undertaken to evaluate the impact of the vaccination program on HBsAg prevalence among school children (∼6 years of age) in Cours Préparatoire (CP). Documented vaccination data were reviewed for all eligible children; children with consent were tested for HBsAg with a rapid point-of-care test. In total, 1,660 students were identified; 1,567 (94%) had vaccination data for review and 1,196 (72%) participated in the serosurvey. Three-dose vaccination coverage was 98%, while timely BD coverage, defined as a dose administered within 24 hours of life, was 89%. Receipt of the second and third doses was often delayed, with 75% and 55% receiving a second and third dose within 1 month of the recommended age, respectively. No children tested positive for HBsAg. French Polynesia's vaccination program has achieved high coverage and an HBsAg seroprevalence of 0% (0-0.5%) among CP school children, but timeliness of vaccination could be improved.

Figure 1.

Enrollment and results of the hepatitis B surface antigen serosurvey, French Polynesia, 2014.

Figure 2.

Vaccination timeliness: cumulative proportion of Cours Préparatoire students vaccinated with each hepatitis B dose by age (in weeks) compared with the EPI Schedule, French Polynesia, 2013–2014. The vertical reference bars indicate age at vaccination recommended by the national program. The first dose was considered timely if it was given within 24 hours of birth; the second dose, if it was given between days 30 and 60 of life; and the third dose, if it was given between days 180 and 210 of life.