Background: The Reveal G4 antibody rapid test is FDA-approved for HIV-1 detection using the versions LAB S/P and POC in CLIA-moderate complexity settings with serum/plasma and whole blood, respectively. The same Reveal tests are CE-marked for HIV-1 and HIV-2 detection in laboratory and point-of-care (POC) settings.
Objective: We compared the performance of G4 LAB S/P with plasma and POC with whole blood (blood) for detecting early and established HIV-1/HIV-2 infections.
Study design: Matched well-characterized plasma and simulated blood were used to evaluate: sensitivity in 104 HIV-1 and 55 HIV-2 established infections, specificity in 49 HIV-negative, and reactivity in early HIV-1 infection in a performance panel (n=38) and 18 plasma panels from seroconverters (SCs, n=183). Median number of days after first RNA-positive was calculated for 13 SCs. Impact of viral suppression (VS) was evaluated in 3 SCs receiving early antiretroviral therapy (ART).
Results: Sensitivity was 100 % for HIV-1 and 98.18 % for HIV-2, while specificity was 100 %. All 38 plasma and blood become reactive by Fiebig stage V. Of 18 SCs, 10 had similar reactivity in plasma/blood, 7 showed delayed reactivity in blood, and 1 was nonreactive in plasma/blood. The median days for a G4-reactive after first RNApositive was 13 for plasma and 14 for blood. Long-term VS had no impact on G4 reactivity.
Conclusions: Overall reactivity in early HIV-1 infections is delayed by one day in blood compared to plasma. If FDA-approved for POC settings, the G4 POC is a fast sensitive screening tool for HIV-1/HIV-2-specific IgG even during VS.
Keywords: HIV diagnostics; HIV-1; HIV-2; Rapid test.
Published by Elsevier B.V.