The ecologic aspects of the distribution of adeno-associated satellite virus (ASV) in the human population are of great interest because of its unconditional defectiveness and dependence on adenovirus for full and herpesvirus for partial complementation. Adenoviruses and herpesviruses are extremely common and persistent infections in man. We have developed immunofluorescent procedures for detecting the presence of satellite virus antibodies in human sera. The percentage of sera with antibodies to the ASV 2-3 complex was significantly higher in the normal group than in the cancer patients whereas there were no significant differences in herpes antibodies between the groups. The low incidence of satellite antibodies was particularly striking in patients with genital malignancies. The role of ASV's in human disease is not known. Their role in possible abrogation of oncogenesis mediated through adenoviruses or herpesviruses is worthy of further investigation.