EVALUATION OF IMMUNOASSAYS FOR DETECTION OF ANTIBODIES TO HUMAN HERPESVIRUS-7

enzyme immunoassay (EIA), an immunoblot assay (IB), and an indirect im munofluorescence assay were developed for detection of human herpesvir us 7 (I4HV 7) antibodies in human serum. Cross-absorption studies with EIA or IFA using HHV-7 and human herpesvirus 6 (HHV-6) antigens indic ated that most human sera contain cross-reactive HHV-6 and HHV-7 antib odies and that the degree of cross-reactivity varies between individua l serum specimens. Inhibition of homologous antibody activity by absor ption with heterologous virus ranged from 0 to 57% by EIA. However, fo r every sample tested, absorption with homologous virus removed more a ctivity than did heterologous virus, An 88-kDa protein was identified as an HHV-7-specific serologic marker by IB. Activity to this protein was not removed by absorption with HHV-6 antigen, Of the three assays, the EIA was the most sensitive (94%), while the IB was the most speci fic (94%). Approximately 80% of specimens collected from German adults and children older than 2 years were positive for HHV-7 antibodies by these assays.