Hepatitis B infection in sub-Saharan Africa. The African Regional Study Group.

Hepatitis B virus (HBV) infection and its sequelae are extremely common in sub-Saharan Africa. The overall hepatitis B surface antigen (HBsAg) carrier rate in the general population is 5-20%, which is amongst the highest in the world. Although perinatal infection occurs with an incidence of 1-5%, the predominant form of transition is horizontal among infants and young children; most infections are acquired between 6 months and the pre-school age (5-6 years). Thus, the traditional concept of 'high-risk groups' is of limited importance in Africa and all children should be regarded as being at risk. Hepatitis B-associated hepatocellular carcinoma is probably the most common tumour affecting males in sub-Saharan Africa, with Mozambique having the highest incidence rate of 103.8 per 100,000 males. Cost-benefit analysis shows that, in sub-Saharan Africa, the most effective way of controlling hepatitis B infection is through mass neonatal vaccination programmes integrated within the Expanded Programme on Immunization without prior testing for HBV markers.