Archiving of mutations in HIV-1 cellular reservoirs among vertically infected adolescents is contingent with clinical stages and plasma viral load: Evidence from the EDCTP-READY study.

INTRODUCTION: Globally, HIV-related adolescent deaths have increased about 50%, especially for those who are vertically infected. This could be driven by archived drug resistance mutations (DRMs) as children grow up, which might jeopardize antiretroviral therapy (ART). Our objective was to compare HIV-1 genotypic variation between plasma RNA and proviral DNA of vertically infected adolescents (aged 10-19 years) failing ART. METHODS: A comparative study was conducted in 2019 among 296 adolescents with perinatal HIV infection (ALPHI) failing ART in health facilities of the Centre Region of Cameroon. The WHO clinical stage, CD4 count and plasma viral load (PVL) were measured. For those failing ART (PVL ≥ 1000 copies/mL), RNA (plasma) and proviral DNA (buffy coat) were sequenced in the pol gene at Chantal BIYA International Reference Centre (CIRCB), Yaoundé, Cameroon. HIV-1 subtypes and DRMs were interpreted using Stanford HIVdb v.8.8 and MEGA-X. RESULTS: Of the 30% (89/296) failing ART, 81 had both RNA and DNA sequences generated and three were excluded for APOBEC mutations: the mean age was 16 ± 3 years; female-to-male ratio was 3:5; median PVL was 46 856 copies/mL [interquartile range (IQR): 19 898-271 410]; median CD4 count was 264 cells/µL (IQR: 131-574); and 42% were at WHO clinical stage 3/4. Subtype concordance between RNA and DNA viral strains was 100%, with CRF02_AG being predominant (65%) and two potential new recombinants found (A1/G/K; F1/G). Adolescents with DRMs were significantly higher in plasma than in proviral DNA (92% vs. 86%, p < 0.0001). Prevalent DRMs by drug class (RNA vs. DNA respectively) were at position M184 (74% vs. 67%) for nucleoside reverse transcriptase inhibitors (NRTIs), K103 (63% vs. 59%) for non-NRTIs, and V82, L76 and M46 (2% vs. 2%) for protease inhibitors. A total of 35% (27/78) of adolescents had concordant DRM profiles in RNA and DNA, while 27% (21/78) had DRMs only in proviral DNA. The presence of archived DRMs was associated with advanced clinical stage 3/4 (OR = 0.14, p = 0.0003) and PVL < 5 Log (Copies/mL) (OR: 4.88, p = 0.006). CONCLUSIONS: Although plasma RNA remains more sensitive for detecting HIV-1 DRMs, about a quarter of ALPHI experiencing ART failure in an African setting might have archived DRMs in viral reservoirs, indicating clinically occult resistance. Thus, to ensure effective ART success, proviral DNA profiling (alongside RNA genotyping) would provide additional DRMs for adolescents with advanced clinical stages and/or moderate PVL.

Pre-existing immunity to SARS-CoV-2 before the COVID-19 pandemic era in Cameroon: A comparative analysis according to HIV-status.

Background: The lower burden of COVID-19 in tropical settings may be due to preexisting cross-immunity, which might vary according to geographical locations and potential exposure to other pathogens. We sought to assess the overall prevalence of SARS-CoV-2 antibodies and determine SARS-CoV-2 seropositivity according to HIV-status before the COVID-19 pandemic era. Methods: A cross-sectional and comparative study was conducted at the Chantal BIYA International Reference Centre (CIRCB) on 288 stored plasma samples (163 HIV-positive versus 125 HIV-negative); all collected in 2017-2018, before the COVID-19 pandemic era. Abbott Panbio™ COVID-19 IgG/IgM assay was used for detecting SARS-CoV-2 immunoglobulin G (IgG) and M (IgM). Among people living with HIV (PLHIV), HIV-1 viral load and TCD4 cell count (LTCD4) were measured using Abbott Real Time PCR and BD FACSCalibur respectively. Statistical analyses were performed, with p<0.05 considered statistically significant. Results: The median [IQR] age was 25 [15-38] years. Overall seropositivity to SARS-CoV-2 antibodies was 13.5% (39/288) of which 7.3% (21) was IgG, 7.3% (21) IgM and 1.0% (3) IgG/IgM. According to HIV-status in the study population, SARS-CoV-2 seropositivity was 11.0% (18/163) among HIV-positive versus 16.8% (21/125) among HIV-negative respectively, p=0.21. Specifically, IgG was 6.1% (10/163) versus 8.8% (11/125), p=0.26; IgM was 5.5% (9/163) versus 9.6%, (12/125), p=0.13 and IgG/IgM was 0.6% (1/163) versus 1.6% (2/125) respectively. Among PLHIV, SARS-CoV-2 seropositivity according to CD4 count was 9.2% (≥500 cells/µL) versus 1.8% (200-499 cells/µL), (OR=3.5; p=0.04) and 0.6% (<200 cells/µL), (OR=17.7; p<0.01). According to viral load, SARS-CoV-2 seropositivity was 6.7% (≥40 copies/mL) versus 4.9% (<40 copies/mL), (OR= 3.8; p<0.01). Conclusion: Before COVID-19 in Cameroon, cross-reactive antibodies to SARS-CoV-2 were in circulation, indicating COVID-19 preexisting immunity. This preexisting immunity may contribute in attenuating disease severity in tropical settings like Cameroon. Of relevance, COVID-19 preexisting immunity is lower with HIV-infection, specifically with viral replication and poor CD4-cell count. As poor CD4-count leads to lower cross-reactive antibodies (regardless of viral load), people living with HIV appear more vulnerable to COVID-19 and should be prioritized for vaccination.