Odusanya O O, Alufohai F E, Meurice F P, Wellens R, Weil J, Ahonkhai V I
Department of Community Health and Primary Care, Lagos State University College of Medicine, P.M.B. 21266 Ikeja, Nigeria.
Int J Infect Dis. 2005 May;9(3):139-43. doi: 10.1016/j.ijid.2004.06.009.
To determine the prevalence of hepatitis B surface antigen (HBsAg) amongst vaccinated children and controls aged 1-4 years in a rural community in mid-western Nigeria.
The vaccinated children had received at least three doses of hepatitis B vaccine. The vaccines included recombinant hepatitis B vaccine at birth and a combined diphtheria, tetanus, pertussis (whole cell) plus hepatitis B (DTPw-HBV) vaccine. HBsAg was determined by a rapid immunoassay method based on the immunochromatographic sandwich principle. Two hundred and twenty-three children and 219 controls were recruited into the study.
The prevalence of HBsAg was significantly lower in the vaccinated group (1.3%) than in the control group (4.6%, p=0.04). The prevalence rates were significantly higher in males (p=0.02) and two-year birth cohort (p=0.01). The controls were estimated to be at a six-fold higher risk of being positive for the surface antigen than the vaccinated children. The vaccine effectiveness was estimated to be approximately 80%.
These results confirm that hepatitis B vaccine protects against hepatitis B surface antigen carriage and confirm immunogenicity of the combined DTPw-HBV vaccine.