Prevalence of hepatitis B virus infection in Nigeria, 2000-2013: a systematic review and meta-analysis.

Vaccination against the hepatitis B virus (HBV) in the West African nation of Nigeria is lower than many Sub-Saharan African countries. In Nigeria, HBV is reported to be the most common cause of liver disease. However, the extent of HBV exposure among Nigerians at average risk is unknown. Our aim, therefore, was to accurately estimate the HBV prevalence for the country and the prevalence for specific subgroups. We used electronic databases to select systematic reviews and meta-analyses from 2000 to 2013. Forty-six studies were included (n = 34,376 persons). We used a random effects meta-analysis of cross-sectional and longitudinal studies to generate our estimates. The pooled prevalence of HBV in Nigeria was 13.6% (95% confidence interval [CI]: 11.5, 15.7%). The pooled prevalence (% [95% CI]) among subgroups was: 14.0% (11.7, 16.3) for blood donors; 14.1% (9.6, 18.6) for pregnant women attending antenatal clinics; 11.5% (6.0, 17.0) for children; 14.0% (11.6, 16.5) among adults; and 16.0% (11.1, 20.9) for studies evaluating adults and children. HBV prevalence in Nigeria varied by screening method [% (95% CI)]: 12.3% (10.1, 14.4) by using enzyme-linked immunosorbent assay; 17.5% (12.4, 22.7) by immunochromatography; and 13.6% (11.5, 15.7) by HBV DNA polymerase chain reaction. HBV infection is hyperendemic in Nigeria and may be the highest in Sub-Sahara Africa. Our results suggest that large numbers of pregnant women and children were exposed to HBV from 2000 to 2013. Increased efforts to prevent new HBV infections are urgently needed in Nigeria.