Low-level of HIV-1 Seroreversion among People on Successful Antiretroviral Therapy in Cameroon: Implications for Clinical Monitoring in Resource-limited Settings

Abstract

Background: Initiating early HIV treatment results to sustained viral suppression, reduced viral reservoirs and prompt immune reconstitution that may lead to HIV seronegativity (seroreversion). Seroreversion can be misinterpreted, leading to inappropriate clinical considerations. We thus sought to determine the HIV seroreversion among antiretroviral therapy (ART)-experienced Cameroonians. Method: A laboratory-based cross-sectional study was conducted among ART-experienced individuals with undetectable plasma viral load (less than 40 copies/mL) in 2019 at the Chantal BIYA International Reference Centre in Yaounde-Cameroon. On all blood samples, HIV antibody testing was performed using two rapid diagnostic tests (RDTs), followed by enzyme-linked immunosorbent assay. On non-reactive samples, proviral DNA was tested on on dried blood spots (DBS) specimens. Results: Of the 546 participants on ART (median ART duration : 5 years) and all experiencing a successful ART (VL<40 copies/ml), only 01% (5/546) had shown HIV negative results. Of these five non-reactive cases, only one case (0.18%) was non-reactive to HIV RDTs but reactive to ELISA, and four cases (0.72%) were non-reactive to both RDTs and ELISA. These four samples were also negative for HIV proviral DNA, indicating potential absence of infection or an optimal control of viral replication. Conclusion: Seroreversion of HIV-1 infection is possible but may occur rarely among HIV-infected Cameroonians who are on successful ART. The few cases of HIV negativity on serology and DBS-PCR (proviral DNA) underscores the need for deeper HIV proviral DNA testing (on PBMC) to guide either continuous ART, detect possible functional cure, or events of HIV misdiagnosis in an era of declining prevalence.