Familial clustering of hepatitis B infection

In a survey among 449 family contacts of blood donors from 197 households containing carriers of hepatitis B antigen, 6.7 per cent were antigen positive, as compared with 0.8 per cent in control households. The greatest prevalence of B antigen was among siblings (19.7 per cent) and other genetic family contacts (8 per cent). In spouses B antigen was less frequently detected (3.4 per cent). Hepatitis B antibody was detected three times more frequently in the study households than in control households. No differences in prevalence of hepatitis B antibody between specific relatives of antigen carriers were seen. Familial clustering does not appear to be correlated with the presence or absence of liver damage in the asymptomatic donor carrier. Neither venereal nor Maternal-Fetal transmission seems to be of primary importance in the spread of hepatitis B infections in these surveyed families. The evidence supports the hypothesis that hepatitis B virus can be transmitted nonparenterally. (N Engl J Med...