Rates of Viral Non-Suppression and Acquired HIV-1 Drug Resistance Emergence among Children during the Sociopolitical Crisis in the Northwest Region of Cameroon: A Call for Improved Monitoring Strategies.

BACKGROUND: Virological failure (VF) among children remains concerning, with high risks of HIV drug resistance (HIVDR) emergence and increased disease progression. Therefore, monitoring of viral non-suppression and emerging HIVDR is crucial, especially in the frame of sociopolitical unrest. OBJECTIVE: The study sought to determine the prevalence of VF and evaluate the acquired HIVDR and viral genetic diversity among children in the northwest region of Cameroon during the ongoing sociopolitical crisis. METHODS: A cross-sectional facility-based study was conducted among HIV-infected children aged ≤18 years, receiving antiretroviral therapy (ART) in urban and rural settings of Northwest Cameroon, from November 2017 through May 2018. Viral load (VL) was done using the Abbott m2000RealTime. Unsuppressed VL was defined as viral load ≥1,000 copies/ml. HIVDR testing was performed by sequencing of HIV-1 protease-reverse transcriptase at the Chantal Biya International Reference Center (CIRCB) using an in-house protocol. Drug resistance mutations (DRM) were interpreted using Stanford HIVdbv8.5 and phylogeny using MEGAv.6. Data were compared between urban and rural areas with p<0.05 considered statistically significant. RESULTS: A total of 363 children were recruited, average age of 12 years (urban) and 8 years (rural). VL coverage was 100% in the urban setting and 77% in the rural setting. Overall, VF was 40.5% (39% [130/332] in the urban setting and 41% (13/31) in the rural setting; p=0.45). Overall, viral undetectability (defined as VL<40 copies/ml) was 45.5% (46% (urban) and 45% (rural); p=0.47). Among those experiencing confirmed virological failure and who were successfully sequenced (n=35), the overall rate of HIVDR was 100% (35/35). By drug class, HIVDR rates were 97.1% (34/35) for non-nucleoside reverse transcriptase inhibitors (NNRTIs), 97.1% (34/35) for NRTIs and 17.1% (6/35) for protease inhibitors (22.7% (5/22) in the urban setting and 7.7% [1/13] in the rural setting). CRF02_AG was the most prevalent viral clade (75%), followed by other recombinants (09_cpx, 11_cpx, 13_cpx, 22_01A1, 37_cpx) and pure subtypes (A1, F2, G, H). CONCLUSION: In this population of children and adolescents living with HIV in a context of socio-political instability in the North-West region of Cameroon, rates of viral non-suppression are high, and accompanied by HIVDR selection. Our suggests the need for a more differentiated care of these CAHIV, especially those in these regions faced with significant socio-economic and health impacts due to the ongoing crisis.

Empowering adolescents living with perinatally-acquired HIV: tailored CD4+ count assessment for optimized care, the EDCTP READY-study.

Background: The elevated rate of AIDS-related mortality in Sub-Saharan Africa among adolescents living with HIV (ALHIV) is influenced by various factors, notably immunosuppression, within a framework of limited therapeutic alternatives. We aimed to enhance the management of pediatric HIV by assessing the immune response and associated factors in perinatally-infected ALHIV on antiretroviral therapy (ART) in Cameroon. Methods: A cohort study was conducted from 2018-2020 among 271 ART-experienced ALHIV in Cameroon. Sociodemographic data, immunological (CD4), and virological (plasma viral load, PVL) responses were measured at enrolment (T0), 6-months (T1), and 12-months (T2) using PIMA CD4 (Abbott/Pantech (Pty) Ltd) and Abbott Applied Biosystem platform (Real-Time PCR m2000RT) respectively. Immunological failure (IF) was defined as absolute CD4 < 250 cells/mm3, and Virological failure (VF) as PVL ≥ 1,000 copies/ml. A linear mixed-effects model with R version 4.4.1 was used to estimate both fixed and random effects, with significance set at p < 0.05. Results: Of the 271 perinatally-infected ALHIV enrolled over three phases, females were predominant (55.7, 55.1, and 56.0%); median age was 14 (IQR: 12-17); majority of the participants were followed-up in urban areas (77.5, 74.5, and 78.6%); and the age distribution favored older adolescents (48.7, 61.2, and 58.5%). Most participants achieved clinical success (93.1, 89.7, 88.9%), predominantly on first-line ART (80.8, 66.2, and 53.0%), with good adherence (64.2, 58.9, and 64.5%). Most participants had secondary education (67.2, 70.1, and 67.5%). Median CD4+ counts fluctuated overtime, with values of 563 (IQR: 249.0-845.0), 502 (IQR: 319.0-783.5), and 628 (IQR: 427.5-817.5), respectively. Of note, being male was linked to a reduction in CD4+ count compared to females, [-200.63 (-379.32 to -21.95), p = 0.028]. Similarly, late adolescence was associated with lower CD4+ counts compared to early adolescence, [-181.08 (-301.08 to -61.09), p = 0.003]. Moreover, participants experiencing VF showed significantly lower CD4+ counts compared to those with undetectable viral loads, [-353.08 (-465.81 to -240.36), p < 0.001]. Additionally, there was a marginally significant interaction between male gender and secondary educational level, [209.78 (-6.94-426.51), p = 0.058]. Conclusion: Among perinatally-infected ALHIV, age, gender, educational level, and virological status are key factors influencing their immune health and treatment outcomes. Prioritizing targeted interventions and close monitoring within these subgroups is crucial for optimal management, employing holistic care strategies that consider not only medical interventions but also psychosocial support and education.

Performance characteristics of INDICAID antigen rapid diagnostic test on SARS-CoV-2 samples during the omicron wave in Cameroon.

Background: WHO recommends the use of COVID-19 antigen rapid diagnostic tests (Ag-RDT) with at least 80 % sensitivity and 97 % specificity. In the era of Omicron variants, we sought to ascertain the performance of the INDICAID™ Ag-RDT compared to real-time PCR (RT-PCR) as the gold standard. Methods: A laboratory-based study was conducted among consenting individuals tested for COVID-19 at the virology laboratory of the Chantal BIYA International Reference Centre, Yaoundé-Cameron. The samples were processed by INDICAID™ Ag-RDT and DaAn Gene real-time PCR according to the manufacturer's instructions, and PCR-results were interpreted as per cycle thresholds (CT). The sensitivity, specificity, positive and negative predictive values (PPV and NVP) of INDICAID™ Ag-RDT were evaluated according to PCR CT-values. Results: A total of 565 nasopharyngeal swabs were collected from participants (median age [IQR]: 40 [31-75]; M/F sex-ratio was 1.2 and 380 were vaccinated). Following PCR, overall COVID-19 positivity was 5.66 %. For CT < 37, INDICAID™ Ag-RDT sensitivity was 21.9 % (95%CI: [8.3-39.9]), specificity 100 % (95%CI: [99.3-100]); PPV 100 % (95%CI: [59.0-100]), NPV 95.5 % (95%CI: [93.4-97.1]) and kappa = 0.34 (95%CI: [0.19-0.35]). For CT < 25, sensitivity was 100 % (95%CI: [47.8-100.0]), specificity 99.6 % (95%CI: [98.7-99.9]); PPV 94.4 % (95%CI: [51.7-100]), NPV 100 % (95%CI: [99.3-100]) and kappa = 0.83 (95%CI: [0.6-1.0]). COVID-19 sequences generated were all Omicron BA.1 subvariants. Conclusion: For patients infected with high viral loads (CT < 25), INDICAID™ Ag-RDT has high intrinsic (sensitivity and specificity) and extrinsic (predictive values) performances for COVID-19 diagnosis. Due to its simplicity and short turnaround time, INDICAID™ Ag-RDT is, therefore a reliable tool to prevent the spread of COVID-19 at community level in the current era of Omicron subvariants.

High performance of integrase genotyping on diverse HIV-1 clades circulating in Cameroon: toward a successful transition to dolutegravir-based regimens in low and middle-income countries.

A successful transition to dolutegravir-based regimens in low and middle-income countries (LMICs) requires an integrase genotyping assay effective on diverse HIV-1 clades. We herein developed and validated an in-house integrase genotyping protocol on plasma samples from 195 HIV-infected patients in Cameroon. Median [IQR] viremia was 23,574 (518-109,235) copies/mL; 128/195 participants had ≥1000copies/mL (i.e., WHO-threshold for genotypic resistance testing in LMICs). A total of 18 viral clades were detected: 72(51.1%) CRF02_AG, 38(26.9%) pure subtypes and 31(22.0%) other recombinants. Following WHO-threshold (≥1000copies/ml), sequencing performance was 82.81%(106/128). Regarding viremia, performance was 85.00%(68/80) with ≥100,000copies/mL versus 76.67%(23/30) with 10,000 to 99,999copies/mL (P = 0.22); 83.33%(15/18) with 1,000 to 99,999copies/mL (P = 0.55); 73.68%(14/19) with 500 to 999copies/mL (P = 0.19); 50%(13/26) for 200 to 499copies/mL (P = 0.0005) and 36.36%(8/22) for <200copies/mL (P < 0.0001). The developed in-house integrase-genotyping is highly effective on both pure and recombinant viral clades, even at low-level viremia. This performance underscores its usefulness in monitoring integrase-resistance mutations and supporting the scale-up of dolutegravir-based regimens in LMICs.

Evaluation of Circulating and Archived HIV-1 Integrase Drug-Resistance Variants among Patients on Third-Line ART in Cameroon: Implications for Dolutegravir-Containing Regimens in Resource-Limited Settings.

To ensure the long-term efficacy of dolutegravir (DTG), we evaluated the genotypic profile in viral reservoirs among patients on third-line (3L) antiretroviral therapy (ART) in Cameroon, according to prior exposure to raltegravir (RAL). A facility-based study was conducted from May through December 2021 among patients on 3L ART from HIV treatment centers in Yaoundé and Douala. Viral load was measured, and genotyping was performed on plasma RNA and proviral DNA. HIV-1 drug resistance mutations were interpreted using HIVdb.v9.1 and phylogeny analysis was performed using MEGA.v7, with P < 0.05 considered significant. Of the 12,093 patients on ART, 53 fully met our inclusion criteria. The median (IQR) age was 51 years (40 to 55 years), and the male/female ratio was 4/5. The median duration on integrase strand-transfer inhibitors (INSTI)-containing regimens was 18 months (12 to 32 months), and 15.09% (8/53) were exposed to RAL. The most administered 3L ART was TDF+3TC+DTG+DRV/r (33.96%, 18/53). Only 5.66% (3/53) had unsuppressed viremia (>1000 copies/mL). Resistance testing in proviral DNA was successful for 18/22 participants and revealed 1/18 patients (5.56%, in the RAL-arm) with archived mutations at major resistance positions (G140R and G163R). Five subtypes were identified, CRF02_AG (12/18), CRF22_01AE (3/18), A1 (1/18), G (1/18), and F2 (1/18). In Cameroon, 3L-experienced patients had a good virological response with a low level of archived mutations in the integrase. This finding underscored the use of DTG-containing ART for heavily treated patients in similar programmatic settings. However, patients with prior exposure to RAL should be closely monitored following a stratified or personalized approach to mitigate risks of INSTI-resistance, alongside pharmacovigilance. IMPORTANCE We described the analysis of the genotypes of the population within third-line antiviral therapy in Cameroon, with a focus on defining the effects of prior raltegravir (RAL) treatment and resistance mutations for current dolutegravir (DTG) treatment. While supporting the current transition to DTG-containing ART in resource-limited settings toward the achievement of the UNAIDS' goal of HIV elimination by 2030, our findings suggested that RAL-exposed patients may need a specific monitoring approach either in a stratified or personalized model of third-line ART to ensure the long-term success of DTG-containing regimens.

Dolutegravir-Based Regimen Ensures High Virological Success despite Prior Exposure to Efavirenz-Based First-LINE ART in Cameroon: An Evidence of a Successful Transition Model.

To ensure optimal prescribing practices in the dolutegravir-era in Cameroon, we compared first-line virological response (VR) under tenofovir + lamivudine + dolutegravir (TLD) according to prior exposure to tenofovir + lamivudine + efavirenz (TLE). A facility-based survey was conducted among patients initiating antiretroviral therapy (ART) with TLD (I-TLD) versus those transitioning from TLE to TLD (T-TLD). HIV viral load was performed and unsuppressed participants (VL > 1000 copies/mL) had genotyping performed by Sanger sequencing. Of the 12,093 patients followed, 310 (mean-age: 41 ± 11 years; 52.26% female) complied with study criteria (171 I-TLD vs. 139 T-TLD). The median ART-duration was 14 (12−17) months among I-TLDs versus 28 (24.5−31) months among T-TLDs (15 (11−19) on TLE and 14 (9−15) on TLD), and 83.15% (148/178) were at WHO clinical stages I/II. The viral suppression rate (<1000 copies/mL) was 96.45%, with 97.08% among I-TLDs versus 95.68% among T-TLDs (p = 0.55). VR was similar in I-TLD versus T-TLD at <400 copies/mL (94.15% versus 94.42%) and age, gender, residence, ART-duration, and WHO stages were not associated with VR (p > 0.05). Genotyping was successful for 72.7% (8/11), with no major mutations to integrase inhibitors found. VR is optimal under first-line TLD after 14 months, even among TLE-exposed, thus confirming the effectiveness of transitioning from TLE to TLD in similar settings, supported by strong pharmacological potency and genetic barrier of dolutegravir.

Diagnostic performance of a colorimetric RT -LAMP for the identification of SARS-CoV-2: A multicenter prospective clinical evaluation in sub-Saharan Africa.

BACKGROUND: 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. METHODS: 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). FINDINGS: 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. INTERPRETATION: 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.