HBsAg positive adopted children as a cause of intrafamilial spread of hepatitis B.

About 5% of the children adopted to Sweden from mostly India and Korea are chronic carriers of HBsAg. Most of them are also e-antigen positive. In this investigation 12 families with such children have been studied to evaluate the infectivity risk. Out of 36 family members 5 have had clinical hepatitis, another 2 were HBsAg positive without clinical symptoms and 15 had anti-HBs. It seems clear that these children are a source of infection and all children adopted from countries with high prevalence of hepatitis B should be screened to be able to define the risk group.