The Asanté™ HIV-1 Rapid Recency® Assay is reliable, feasible, and acceptable for use at the point-of-care in Lusaka, Zambia.

Abstract

BACKGROUND: Zambia established a recent infection testing algorithm (RITA) incorporating a novel point-of-care (POC) rapid test-the Asanté™ HIV-1 Rapid Recency® Assay (RTRI)-plus a HIV-1 viral load (VL) test to distinguish recent (≤12 months) from long-term (>12 months) HIV acquisition. This study evaluated the field performance of RTRI when implemented by healthcare workers at the POC.

METHODS: We enrolled individuals newly diagnosed with HIV between 20 May 2021 and 10 March 2022 at two Ministry of Health facilities in Lusaka, Zambia. Participants received on-site RTRI testing and provided an additional sample for repeat RTRI and VL testing at a central laboratory. Final recent infection testing algorithm (RITA) results were returned to the study sites and were made available to clients at their study follow-up visit. Agreement between POC- and laboratory-RTRI was assessed using Cohen's Kappa. We compared recent versus long-term HIV classification across testing locations using the national RITA as the reference standard. Four focus group discussions (FGDs) with health staff explored perceptions surrounding POC-RTRI implementation.

RESULTS: Agreement between POC and laboratory RTRI was 96.5%, with a Kappa of 0.812 (95% CI: 0.704-0.920). The POC-RTRI results indicated numerically more recent infections than laboratory-RTRI (30 vs 27), with three POC-RTRI false positives resulting in reduced sensitivity 85.0% for the POC-RTRI compared to 100.0% sensitivity for the laboratory-RTRI against the RITA reference standard. FGD participants (n = 28) agreed that POC RTRI was feasible and acceptable with adequate training, human resources, client counselling, and quality assurance measures.

CONCLUSION: There was strong concordance between POC- and laboratory-RTRI results. The findings support the feasibility of implementing RTRI at POC by non-laboratory health workers, provided adequate training and health system resources are in place.