DETECTION OF ANTIBODIES TO HUMAN-IMMUNODEFICIENCY-VIRUS IN VAGINAL SECRETIONS BY IMMUNOGLOBULIN-G ANTIBODY-CAPTURE ENZYME-LINKED-IMMUNOSORBENT-ASSAY - APPLICATION TO DETECTION OF SEMINAL ANTIBODIES AFTER SEXUAL INTERCOURSE

In order to evaluate a commercial immunoglobulin G (IgG) antibody capt ure enzyme-linked immunoassay (ELISA) (Wellcozyme HIV1+2 Gacelisa; Mur ex Diagnostics Limited, Dartford, United Kingdom) for the detection of antibodies to human immunodeficiency virus (HIV) in vaginal secretion samples (VS) from HIV-seropositive and -seronegative women, serum sam ples (S) and VS a ere obtained from 129 African women living in the Ce ntral African Republic, a country of high HN prevalence. Sera were tes ted for HIV by routine second-generation ELISA with confirmatory Weste rn blot (immunoblot) (WB). By the Gacelisa IgG immunocapture assay, 45 VS were positive and 84 were negative, whereas by WB, 44 VS were conf irmed positive and 85 were confirmed negative. Considering WB as a ref erence, the IgG immunocapture assay in VS was 97.7% sensitive (43 of 4 4 positive samples) and 97.6% specific (83 of 85 negative samples). Of 42 HIV-seropositive women, 41 (97.6%) had S and VS that both were HIV positive (S+ VS+), and of 87 HIV-seronegative women, 83 (95.4%) had S and VS that both were HIV negative (S- VS-). Five women had discordan t results for S and VS. One (S+ VS-) possibly had a false-negative VS result. Two (S- VS+) had similar indeterminate patterns for S and VS i n WB. Two (S- VS+) had a typical HIV-positive pattern on WB of VS, whe reas S results in WB were indeterminate in one case and negative in th e other case; for both women, detection of prostatic acid-phosphatase was positive in VS, strongly suggesting recent sexual intercourse with an HIV-positive man. HIV1+2 Gacelisa appears to be a useful, reliable assay to detect IgG antibodies to HIV in VS from HIV-infected nomen, in whom the anti-HN IgG antibodies are largely predominant. This assay could also serve to detect IgG antibodies to HIV in VS from a non-HIV -infected woman who has had recent sexual intercourse with an HN-infec ted man. Because all HIV-infected men have detectable IgG antibodies t o HIV in the seminal fluid, an HN-seronegative rape victim with HIV-po sitive VS (S- VS+) should receive short-term antiviral therapy to prev ent possible HIV transmission.