Hepatitis C Virus (HCV) is the principal agent of non-A, non-B hepatitis and its spread in the community is not well defined. We evaluated the prevalence of anti-HCV (ortho ELISA System) in 696 children (4-14 years) in Kumba, Cameroon. Children were selected by systematic random sampling in six primary schools. A seroprevalence of 14.5% (101 children) was found which increased steadily with age. No significant differences were observed with respect to sex or to family size. There was a highly significant association both with parents' social class, the lowest class presenting a 2.2-fold risk factor, and with area of residence, suburban children showing a significantly higher prevalence (P less than 0.01). These results suggest that Cameroon is endemic for HCV infection, that children are infected at an early age and that infection increases with age. We can therefore hypothesize that transmission of HCV infection in this population is from child to child. Furthermore, the infection seems to be influenced by social factors but not by demographic ones.