Background: After the launching of the « Test & Treat » strategy and the wider accessibility to viral load (VL), evaluating virological success (VS) would help in meeting the UNAIDS targets by 2020 in Cameroon. Setting and methods: Cross-sectional study conducted in the Chantal BIYA International Reference Centre for research on HIV/AIDS prevention and management (CIRCB), Yaoundé, Cameroon; data generated between October 2016 and August 2017 amongst adults, adolescents and children at 12, 24, 36 and ≥ 48 months on ART. VS was defined as < 1000 copies/mL of blood plasma and controlled viremia as VL < 50 copies/mL. Data were analysed by SPSS; p < 0.05 considered as significant. Results: 1946 patients (70% female) were enrolled (1800 adults, 105 adolescents, 41 children); 1841 were on NNRTI-based and 105 on PI-based therapy; with 346 patients at M12, 270 at M24, 205 at M36 and 1125 at ≥ M48. The median (IQR) duration on was 48 months (24–48). Overall, VS was 79.4% (95% CI 77.6–81.2) and 67.1% (95% CI 64.9–69.1) had controlled viral replication. On NNRTI-based, VS was 79.9% vs. 71.4% on PIs-based, p = 0.003. By ART duration, VS was 84.1% (M12), 85.9% (M24), 75.1% (M36) and 77.2% (≥ M48), p = 0.001. By age, VS was 75.6% (children), 53.3% (adolescents) and 81.1% (adults), p < 0.001. Conclusions: In this sub-population of patients receiving ART in Cameroon, about 80% might be experiencing VS, with declining performance at adolescence, with NNRTI-based regimens, and as from 36 months on ART. Thus, improving VS may require an adapted adherence support mechanism, especially for adolescents with long-term treatment in resource-limited settings.

The majority (>95%) of new HIV infection occurs in resource-limited settings, and Cameroon is still experiencing a generalized epidemic with ~122,638 patients receiving antiretroviral therapy (ART). A detrimental outcome in scaling-up ART is the emergence HIV drug resistance (HIVDR), suggesting the need for pragmatic approaches in sustaining a successful ART performance. A survey was conducted in 15 ART sites of the Centre and Littoral regions of Cameroon in 2013 (10 urban versus 05 rural settings; 8 at tertiary/secondary versus 7 at primary healthcare levels), evaluating HIVDR-early warning indicators (EWIs) as-per the 2012 revised World Health Organization’s guidelines: EWI₁ (on-time pill pick-up), EWI₂ (retention in care), EWI₃ (no pharmacy stock-outs), EWI₄ (dispensing practices), EWI₅ (virological suppression). Poor performance was interpreted as potential HIVDR. Only 33.3% (4/12) of sites reached the desirable performance for “on-time pill pick-up” (57.1% urban versus 0% rural; p<0.0001) besides 25% (3/12) with fair performance. 69.2% (9/13) reached the desirable performance for “retention in care” (77.8% urban versus 50% rural; p=0.01) beside 7.7% (1/13) with fair performance. Only 14.4% (2/13) reached the desirable performance of “no pharmacy stock-outs” (11.1% urban versus 25% rural; p=0.02). All 15 sites reached the desirable performance of 0% “dispensing mono- or dual-therapy”. Data were unavailable to evaluate “virological suppression” due to limited access to viral load testing (min-max: <1%-15%). Potential HIVDR was higher in rural (57.9%) compared to urban (27.8%) settings, p=0.02; and at primary (57.9%) compared to secondary/tertiary (33.3%) healthcare levels, p=0.09. Delayed pill pick-up and pharmacy stock-outs are major factors favoring HIVDR emergence, with higher risks in rural settings and at primary healthcare. Retention in care appears acceptable in general while ART dispensing practices are standard. There is need to support patient-adherence to pharmacy appointments while reinforcing the national drug supply system.

Management and control of the COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus SARS-CoV-2 is critically dependent on quick and reliable identification of the virus in clinical specimens. Detection of viral RNA by a colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) is a simple, reliable and cost-effective assay, deployable in resource-limited settings (RLS). Our objective was to evaluate the intrinsic and extrinsic performances of RT-LAMP in RLS. This is a multicenter prospective observational study of diagnostic accuracy, conducted from October 2020 to February 2021 in four African Countries: Cameroon, Ethiopia, Kenya and Nigeria; and in Italy. We enroled 1657 individuals who were either COVID-19 suspect cases, or asymptomatic and presented for screening. RNA extracted from pharyngeal swabs was tested in parallel by a colorimetric RT-LAMP and by a standard real time polymerase chain reaction (RT-PCR). The sensitivity and specificity of index RT LAMP compared to standard RT-PCR on 1657 prospective specimens from infected individuals was determined. For a subset of 1292 specimens, which underwent exactly the same procedures in different countries, we obtained very high specificity (98%) and positive predictive value (PPV = 99%), while the sensitivity was 87%, with a negative predictive value NPV = 70%, Stratification of RT-PCR data showed superior sensitivity achieved with an RT-PCR cycle threshold (Ct) below 35 (97%), which decreased to 60% above 35. In this field trial, RT-LAMP appears to be a reliable assay, comparable to RT-PCR, particularly with medium-high viral loads (Ct < 35). Hence, RT-LAMP can be deployed in RLS for timely management and prevention of COVID-19, without compromising the quality of output. Bill & Melinda Gates Foundation [Grant No. INV-022,816].

Enhancing the clinical trial capabilities within Africa is essential to augment the continent’s pandemic prevention, preparedness and response efforts. Here, we describe the critical challenges of clinical trials in Africa and draw upon the lessons learnt from the Consortium for COVID-19 Vaccine Clinical Trials (CONCVACT) experience, such as the importance of regional collaboration, capacity building and establishing standardized protocols.

Scale-up of antiretroviral therapy (ART) in resource-limited settings has drastically reduced HIV-related morbidity and mortality. However, challenges in long-term ART, adherence and HIV drug resistance (HIVDR) itself, require monitoring to limit HIVDR emergence among ART-experienced populations, in order to ensure regimen efficacy. A longitudinal study was conducted from 2009–2011 in a cohort of 141 HIV-infected adult patients (aged >21) at the national social insurance centre hospital in Yaounde, Cameroon. As per-WHO HIVDR protocol, HIV-1 protease-reverse transcriptase genotyping was performed at baseline and at endpoint (12 months) on first-line ART using ViroSeq™ Genotyping kit. At baseline, a prevalence of 3.6% (5/139) HIVDR was observed [protease inhibitors M46I (1/5), G73A (1/5), L90LM (1/5); nucleoside reverse transcriptase inhibitors: M184V (1/5), T215F (1/5); non-nucleoside reverse transcriptase inhibitors: K103N (1/5), Y181Y/C (2/5), M230ML (1/5)]. At endpoint, 54.0% (76) patients were followed-up, 9.2% (13) died, and 3.5% (5) transferred, 38.5% (47) lost to follow-up (LTFU). 69.7% (53/76) of those followed-up had viremia <40 copies/ml and 90.8% (69/76) <1000 copies/ml. 4/7 patients with viremia ≥1000 copies/ml harbored HIVDR (prevalence: 5.3%; 4/76), with M184V/I (4/4) and K103K/N (3/4) being the most prevalent mutations. LTFU was favored by costs for consultation/laboratory tests, drug shortages, workload (physician/patient ratio: 1/180) and community disengagement. Low levels of HIVDR at baseline and at endpoint suggest a probable effectiveness of ART regimens used in Cameroon. However the possible high rate of HIVDR among LTFUs limited the strengths of our findings. Evaluating HIVDR among LTFU, improving adherence, task shifting, subsidizing/harmonizing costs for routine follow-up, are urgent measures to ensure an improved success of the country ART performance.

Aim: To investigate the prevalence and genotypic profile of overt and occult hepatitis-B infection (OBI) among HIV-infected individuals in Cameroon. Methods: 212 HIV-infected Cameroonians, aged 37.6 [IQR: 32.6-46.6] followed-up at the University Health Centre in Yaoundé, were tested for HBsAg, anti-HBs, anti-HBc IgG/IgM, HBV-DNA and anti-HCV IgG. HBV positive cases were tested for Hepatitis Delta virus (HDV) using anti-HDV IgG and HDV-RNA. Liver function was assessed by alanine and aspartate aminotransaminases. OBI was defined as negative-HBsAg and detectable HBV-DNA. In occult or overt HBVinfected participants, HBV reverse transcriptase (RT)/surface (S) sequences were analyzed for drug resistance, immuneescape mutants, and phylogeny. Results: Overall, 78.3% (166/212) participants had past/ongoing HBV-exposure, with 39.1% (83/212) carrying “HBcAbpositive alone”. Prevalence of overt HBV (positive-HBsAg) was 11.8% (25/212), prevalence of HBV and HDV was respectively 6.9% (12/175) and 12% (3/25). Phylogeny of HBV-RT/S revealed the co-circulation of genotypes A and E. All HBV-coinfected participants harbored HBV strains with at least one immune-escape mutation. Of note, one HBV variant carried the vaccine-escape mutation G145R that hinders HBsAg neutralization by antibodies. For the first time, a novel 9 aa-deletion (s115-s123), located in the HBsAg “a” determinant, was found concomitantly with OBI. A stop codon in the S region (associated with increased risk of hepatocellular carcinoma) was found in six cases. Conclusion: High prevalence of overt/occult HBV-infection and circulating atypical strains highlight the importance of HBV-surveillance among HIV-infected Cameroonians and strategies to detect OBI in highly endemic countries.