Prevalence of serum antibodies to herpes simplex virus types 1 and 2: application of an ELISA technique to 100 cases of anogenital herpes.

Sera of 100 patients affected by anogenital herpes were tested by an enzyme-linked immunosorbent assay (ELISA) technique using partially purified antigens obtained by extraction from the nuclei of infected Vero cells. Herpes simplex virus type 1 (HSV-1) was isolated from the anogenital lesions of 17 patients and herpes simplex virus type 2 (HSV-2) from 83 patients. The relative proportions of antibody of the IgG class to HSV-1 and HSV-2 were determined and their ratio (R) was calculated, except for 23 patients for whom the corrected optical density (COD) obtained for HSV-1 or HSV-2 antibody was less than the lower value limit of 0.025. A predominance of HSV-2 antibody (R less than 1) was found in 40 patients and was uniformly associated with isolation of HSV-2, whereas a predominance of HSV-1 antibody (R greater than 1) in 37 patients was found in the presence of infection with HSV-1 in 11 (30%) and with HSV-2 in 26 (70%) patients. This study also confirms the association of a higher frequency of recurrences with HSV-2: among the 55 patients with recurrent herpes, those from whom HSV-2 was isolated had a history of more recurrences than those infected with HSV-1 (P less than 0.05; Mann and Whitney's nonparametric test). No correlation between the number of recurrences and the level of HSV-2 antibody was found.