1454 Hepatitis B Vaccination Effectiveness in Greenland

Background and aims: Greenland is a hepatitis B (HBV) high-endemic country, but the only preventive measure against HBV is routine HBsAg testing of pregnant women and HBV vaccination of children born to HBsAg positive mothers. Methods: This national wide study evaluated the effectiveness of the Hepatitis B vaccination program in Greenland by examine the frequency of HBsAg testing during pregnancy of all live-births from 1992 to 2000. Secondly we followed-up children born to HBsAg positive mothers in Greenland in the period 1992 to 2007 and determined their vaccination- and HBV status. Results: The survey revealed more challenges in the Greenlandic HBV vaccination program. Firstly, only 65% of all live births were preceded by HBV testing of the mother during pregnancy. Secondly in the follow up study of children born to HBsAg positive mothers, we found that 20% had received no vaccination at all, and that only 58% of the children had received three or four vaccinations. Thirdly, 3% of the children born to HBsAg positive mothers were immune and 3% were chronically infected. Fourthly, the HBsAb level of immunized children was unexpectedly low indicating non responders or an ineffective vaccine. Conclusions: Based on the results in this study we therefore urgently recommend changing the HBV vaccination strategies in Greenland. HB vaccination should be included in the childhood vaccination program and the procedures in the general screening programme of pregnant women should be evaluated and there should be an attenuated awareness of atrisk children born to HBsAg positive mothers.