From: Efficacy and effectiveness of infant vaccination against chronic hepatitis B in the Gambia Hepatitis Intervention Study (1986–90) and in the nationwide immunisation program
Years of age in 2007–08 (and median birth year)
HBsAg positivity/number tested (%)
1- 5 (2005)
3/1921 (0.2%)
5- 9 (2001)
6/1591 (0.4%)
10-14 (1996)
10/ 825 (1.2%)
15-17 (1993)
5/ 276 (1.8%)
1-17 (2002)
24/4613 (0.5%)