[Hepatitis B in children].

Central to immunization programmes is that hepatitis B virus infection in infancy is much more likely to result in the chronic carrier state than if infection occurs in adulthood. In areas of high endemicity like south-eastern Asia most infections occur when chronically infected women transmit hepatitis B virus to their newborns or when chronically infected children transmit the virus to other children. In the Netherlands, the endemicity is considered low; seroprevalence studies showed that 0.8% of the pregnant women are HBsAg-positive. To prevent mother to child transmission of hepatitis B a national immunization program has recently been implemented to prevent perinatal infection in approximately 450 neonates each year. Horizontal transmission of hepatitis B virus also seems possible in children since persistent carriers are found in (medical) centres and institutions for mentally handicapped. Since hepatitis B infections acquired during early childhood are likely to progress to chronicity and liver disease in adult life some risk factors for children in the Netherlands to contract hepatitis B infection are described and the immunization strategy is discussed.