An update after 16 years of hepatitis B vaccination in South Africa

Abstract

Hepatitis B (HB) virus (HBV) infection is highly endemic with at least 65 million chronic HB surface antigen (HBsAg) carriers in Africa, 25% of whom are expected to die from liver disease. Before the introduction of the HB vaccine, the prevalence of chronic carriage of HBV in black South Africans was 9.6%, with 76% having been previously exposed to HBV. The major transmission route in South Africa is unexplained horizontal transmission between toddlers, with most transmission occurring before the age of 5 years. During adolescence and early adulthood, sexual transmission becomes the dominant route, while healthcare workers (HCWs) are also at risk for parenteral/percutaneous transmission during occupational exposures. In 1995 the South African Department of Health (SADoH) incorporated the HB vaccine, administered as a monovalent, into the Expanded Programme on Immunisation (EPI) at 6, 10, and 14 weeks of age, and studies conducted thereafter have found it to be safe and highly effective. Catch-up vaccination for adolescents was not introduced and there is no schools-based vaccination programme. The SADoH recommends HB vaccination of HCWs, but this is not mandatory and there is no national policy, thus HB vaccination uptake in HCWs is sub-optimal. Since 1995, studies on children have found that the prevalence of chronic HBsAg carriage has decreased, as has the incidence of paediatric hepatocellular carcinoma and HBV-related membranous nephropathy. The SADoH should focus their efforts on attaining a high infant HB vaccine coverage, prepare for introducing a HB birth dose, and consider using a hexavalent vaccine (DTaP-IPV-Hib-HepB). The department may also want to consider including targeted HB vaccination for 12 year-olds, if their Road to Health Cards show they were not vaccinated as infants. A national policy is needed for HCWs to ensure that they are fully vaccinated and protected against HBV infection.