Objective: To determine the effectiveness and impact of the Dutch childhood hepatitis B virus (HBV) vaccination policy targeted at children with at least one parent born in an HBV endemic country.
Methods: The Dutch vaccination registration database was used to determine vaccine coverage for HBV and DTP-IPV-Hib in the target population. HBV notifications were used to estimate the impact. We determined the HBV incidence in children aged 0 to 4 years and born after (2003 - 2007) and before (1990 - 2002) the introduction of the HBV vaccination programme.
Results: HBV vaccine coverage in the target population was 89.6% (96,186/107,338) in the period 2003 to 2005. There were 37 notified acute infections in the pre-vaccination birth cohort 1990 to 2002 (incidence = 2.9/106 person years), compared to 1 in the post-vaccination birth cohort 2003 to 2007 (incidence = 0.3/106 person years). The incidence rate ratio (IRR) for the 2003 to 2007 birth cohort vs. the 1990 to 2002 birth cohort was 0.12 (95% CI: 0.02 to 0.87; p=0.04).
Conclusions: We show that the incidence of HBV notifications in children born after the introduction of targeted childhood HBV vaccinations is lower compared to the incidence in children born before the start of this vaccination programme. Although this is consistent with a good HBV vaccine coverage the interpretation is hampered by change in case definition for notification in 1999. Our results are of importance to policy makers in both The Netherlands and other countries that have a targeted HBV vaccination programme.