Use of the Bio-Rad Geenius HIV-1/2 supplemental assay for the testing of oral fluids for the presence of HIV antibody

Abstract

There is currently an absence of products which are cleared by the FDA to provide supplemental testing for oral fluid for HIV antibody. We created a procedure for the use of the BioRad Geenius HIV-1/2 as a supplemental antibody test for oral fluid specimens. The modified procedure was evaluated for its ability to detect HIV-1 antibody in oral fluid in specimens that were found to be repeatedly reactive for HIV-1 antibody by way of the Avioq HIV-1 enzyme immunoassay (EIA). Evaluated were oral fluid specimens analyzed at a local public health laboratory which were stored frozen and oral fluid specimens collected prospectively. Prospectively collected specimens were from patients whose HIV status was subsequently assessed through blood-based testing. For retrospective specimens found repeatedly EIA reactive, and positive by Western blot, the modified Geenius was found positive in 37/38 instances (97.4 %). Those specimens with a mean EIA signal-to-cutoff (S/CO) greater than 3.00 were found to be positive by Geenius in 34/34 (100 %) of instances. For specimens found repeated reactive by EIA and positive by Western blot with mean S/CO less than or equal to 3.00, the Geenius was positive in 4/5 instances (80 %) of instances. For prospectively collected specimens, the Geenius accurately confirmed infection in 22/24 cases (92 %) while prospective specimens found repeatedly reactive by EIA without supplemental Geenius testing were confirmed positive in 29/37 instances (78 %). A modified usage of the Geenius HIV-1/2 Supplemental Assay antibody test may provide utility in the supplementation of testing of oral fluid for the presence of HIV-1 antibody.