Ezechiel Ngoufack Jagni Semengue

Dr. Ezechiel Ngoufack Jagni Semengue

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 August 2023 in Pathogens
Verified
Journal Article
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MTMichel Carlos TOMMO TCHOUAKET
Michel Carlos TOMMO TCHOUAKET
AKAude Christelle Ka'e
Aude Christelle Ka'e
ESEzechiel Ngoufack Jagni Semengue
Ezechiel Ngoufack Jagni Semengue
SSSamuel Martin Sosso
Samuel Martin Sosso
RSRachel Kamgaing Simo
Rachel Kamgaing Simo
JFJoseph Fokam
Joseph Fokam
Background: Sub-Saharan Africa (SSA) carries the highest burden of high-risk human papillomavirus (HR-HPV) in the world, driven by, and together with, HIV infection. This systematic review aimed to identify HR-HPV genotypes and their associated factors among women in SSA. Methods: A systematic review and meta-analysis of studies conducted in SSA on HR-HPV was conducted. Standard electronic databases were searched. R software version 3.6.0 was used for meta-analysis, with p < 0.05 considered statistically significant. Results: We included 28 articles with a total of 22,652 participants. The overall pooled prevalence of HR-HPV genotypes was 55.13%, albeit high heterogeneity between studies. The overall pooled prevalence of HR-HPV genotypes in HIV-positive individuals was 75.51%, compared to 52.97% in HIV-negatives (OR = 4.68 (0.71–30.76)). HPV 16 (18%), 35 (10.12%), 52 (9.98%), 18 (9.7%) and 45 (6.82%) genotypes were the most prevalent. Twelve studies identified the most frequently reported risk factors associated with HR-HPV, with HIV infection (66.66%), multiple sexual partners (41.66%) and young age (41.66%) being the most reported risk factors. Conclusions: The combined prevalence of HR-HPV genotypes among women in general and HIV-infected women in particular remains high in SSA. The presence of several genotypes not covered by the vaccine is remarkable and suggests the need for revision of current vaccination policies to prevent HR-HPV infections.

19 May 2023 in Medicine
Verified
Journal Article
Open access
JFJoseph Fokam
Joseph Fokam
ANAlex Durand NKA
Alex Durand NKA
FDFlore Yollande Bmls Mamgue Dzukam
Flore Yollande Bmls Mamgue Dzukam
JGJeremiah Bmls Efakika Gabisa
Jeremiah Bmls Efakika Gabisa
YBYagai Bouba
Yagai Bouba
ANAlexis Ndjolo
Alexis Ndjolo
This study aimed to compare viral suppression (VS) between children, adolescents, and adults in the frame of transition to dolutegravir (DTG)-based antiretroviral therapy (ART) in the Cameroonian context. A comparative cross-sectional study was conducted from January 2021 through May 2022 amongst ART-experienced patients received at the Chantal BIYA International Reference Centre in Yaounde-Cameroon, for viral load (VL) monitoring. VS was defined as VL < 1000 copies/mL and viral undetectability as VL < 50 copies/mL. Chi-square and multivariate binary logistic regression models were used to identify factors associated with VS. Data were analyzed using SPSS v.20.0 (SPSS Inc., Chicago, Illinois), with P < .05 considered significant. A total of 9034 patients (72.2% females) were enrolled. In all, there were 8585 (95.0%) adults, 227 (2.5%) adolescents, and 222 (2.5%) children; 1627 (18.0%) were on non-nucleoside reverse transcriptase-based, 290 (3.2%) on PI-based, and 7117 (78.8%) on DTG-based ART. Of those on DTG-based ART, only 82 (1.2%) were children, 138 (1.9%) adolescents, and 6897 (96.9%) adults. Median (interquartile range) duration on ART was 24 (12–72) months (24 months on Tenofovir + Lamivudine + Dolutegravir [TLD], 36 months on other first lines, and 84 months on protease inhibitors boosted with ritonavir-based regimens). Overall, VS was 89.8% (95% confidence interval: 89.2–90.5) and viral undetectability was 75.7% (95% confidence interval: 74.8–76.7). Based on ART regimen, VS on Non-nucleoside reverse transcriptase-based, protease inhibitors boosted with ritonavir-based, and DTG-based therapy was respectively 86.4%, 59.7%, and 91.8%, P < .0001. Based on ART duration, VS was respectively 51.7% (≤24 months) versus 48.3% (≥25 months), P < .0001. By gender, VS was 90.9% (5929) in females versus 87.0% (2183) in males, P < .0001; by age-range, VS moved from 64.8% (144) in children, 74.4% (169) adolescents, to 90.8% (7799) adults, P < .0001. Following multivariate analysis, VS was associated with adulthood, female gender, TLD regimens, and combination antiretroviral therapy duration > 24 months (P < .05). In Cameroon, ART response indicates encouraging rates of VS (about 9/10) and viral undetectability (about 3/4), driven essentially by access to TLD based regimens. However, ART response was very poor in children, underscoring the need for scaling-up pediatric DTG-based regimens.

21 December 2022 in Viruses
Verified
Journal Article
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ESEzechiel Ngoufack Jagni Semengue
Ezechiel Ngoufack Jagni Semengue
JFJoseph Fokam
Joseph Fokam
NENaomi-Karell Etame
Naomi-Karell Etame
Evariste MolimbouEvariste Molimbou
Evariste Molimbou
CACollins Chenwi Ambe
Collins Chenwi Ambe
ANAlexis Ndjolo
Alexis Ndjolo
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 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.

11 October 2022 in PLOS Global Public Health
Verified
Journal Article
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ESEzechiel Ngoufack Jagni Semengue
Ezechiel Ngoufack Jagni Semengue
MSMaria Mercedes Santoro
Maria Mercedes Santoro
VNValantine Ngum Ndze
Valantine Ngum Ndze
AKAude Christelle Ka’E
Aude Christelle Ka’E
YBYagai Bouba
Yagai Bouba
JFJoseph Fokam
Joseph Fokam
As sub-Saharan Africa (SSA) countries are transitioning to dolutegravir (DTG)-based ART, baseline data are required for optimal monitoring of therapeutic response. In this frame, we sought to generate up-to-date evidence on the use of integrase-strand transfer inhibitors (INSTI) and associated drug resistance mutations (DRMs) within SSA. In this systematic review and meta-analysis, we included randomized and non-randomized trials, cohort-studies, cross-sectional studies, and case-reports published on INSTI or integrase DRMs in SSA. We included studies of patients exposed to DTG, raltegravir (RAL) or elvitegravir (EVG). Primary outcomes were “the rate of virological control (VC:<50copies/ml)” and “the presence of DRMs” on INSTI-based regimens among patients in SSA. We synthesised extracted data using subgroup analysis, and random effect models were used where appropriate. Additional analyses were conducted to assess study heterogeneity. We identified 1,916 articles/citations through database searches, of which 26 were included in the analysis pertaining to 5,444 patients (mean age: 37±13 years), with 67.62% (3681/5444) female. Specifically, 46.15% (12/26) studies focused on DTG, 26.92% (7/26) on RAL, 23.08% (6/26) on both DTG and RAL, and 3.85% (1/26) on EVG. We found an increasing use of DTG overtime (0% before 2018 to 100% in 2021). Median treatment duration under INSTI-based regimens was 12 [9–36] months. Overall, the rate of VC was 88.51% [95%CI: 73.83–97.80] with DTG vs. 82.49% [95%CI: 55.76–99.45] and 96.55% [95%CI: 85.7–100.00] with RAL and EVG, respectively. In univariate analysis, VC with DTG-containing vs. other INSTI-regimens was significantly higher (OR = 1.44 [95%CI: 1.15–1.79], p = 0.0014). Among reported DRMs at failure, the only DTG resistance-mutations were G118R and R263K. In SSA, DTG presents a superiority effect in VC compared to other INSTIs. Nonetheless, the early detection of INSTI-DRMs calls for sentinel surveillance for a successful transition and a sustained efficacy of DTG in SSA. PROSPERO Registration Number: CRD42019122424.

28 June 2023 in Viruses
Verified
Journal Article
Open access
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JFJoseph Fokam
Joseph Fokam
CACollins Chenwi Ambe
Collins Chenwi Ambe
VTValère Tala
Valère Tala
DTDésiré Takou
Désiré Takou
MSMaria Santoro
Maria Santoro
ANAlexis Ndjolo
Alexis Ndjolo
The efficacy of first-line antiretroviral therapy (ART) may be hampered by the presence of HIV drug resistance (HIVDR). We described HIV-1 pre-treatment drug resistance (PDR) patterns, effect of viral clades on PDR, and programmatic implications on first-line regimens in Cameroon. A sentinel surveillance of PDR was conducted from 2014 to 2019. Sequencing of HIV-1 protease and reverse transcriptase was performed, and HIVDR was interpreted using Stanford HIVdb.v.9.4. In total, 379 sequences were obtained from participants (62% female, mean age 36 ± 10 years). The overall PDR rate was 15.0% [95% CI: 11.8–19.0] nationwide, with significant disparity between regions (p = 0.03). NNRTI PDR was highest (12.4%), of which 7.9% had DRMs to EFV/NVP. Two regions had EFV/NVP PDR above the 10% critical threshold, namely the Far North (15%) and East (10.9%). Eighteen viral strains were identified, predominated by CRF02_AG (65.4%), with no influence of genetic diversity PDR occurrence. TDF-3TC-DTG predictive efficacy was superior (98.4%) to TDF-3TC-EFV (92%), p < 0.0001. The overall high rate of PDR in Cameroon, not substantially affected by the wide HIV-1 genetic diversity, underscores the poor efficacy of EFV/NVP-based first-line ART nationwide, with major implications in two regions of the country. This supports the need for a rapid transition to NNRTI-sparing regimens, with TDF-3TC-DTG having optimal efficacy at the programmatic level.

6 October 2022 in IJID Regions
Verified
Journal Article
Open access
MTMichel Carlos TOMMO TCHOUAKET
Michel Carlos TOMMO TCHOUAKET
JFJoseph Fokam
Joseph Fokam
SSSamuel Martin Sosso
Samuel Martin Sosso
ESEzechiel Ngoufack Jagni Semengue
Ezechiel Ngoufack Jagni Semengue
YBYagai Bouba
Yagai Bouba
ANAlexis Ndjolo
Alexis Ndjolo
The burden of human papillomavirus (HPV) is high in Cameroon, but knowledge on high-risk oncogenic HPV (HR-HPV) is limited. Our study sought to ascertain the HR-HPV genotypes circulating in Cameroon. A cross-sectional study was conducted among non-vaccinated women in Cameroon. Detection of HR-HPV was performed by real-time PCR on cervico-vaginal swabs. Predictors of HR-HPV were determined following logistic regression analysis, with p < 0.05 considered statistically significant. In total, 364 women were enrolled, with a median age of 41 (34–50) years. Of these, 3.0% were smokers and 26.09% reported having more than three sexual partners. The overall HR-HPV positivity rate was 21.43% (95% CI 17.21–25.64). Predictors of HR-HPV were young age, i.e < 41 years (aOR (95% CI) 0.408 (0.194–0.862); p = 0.018), smoking (aOR 5.199 (1.314–20.575); p = 0.018), and having more than three sex partners (aOR: 2.335 (1.133–4.811); p = 0.022). Overall, 12 HR-HPV genotypes were identified, with 26.98% women coinfected with at least two HR-HPVs, including one case of a triple coinfection. According to to the circulating genotypes, potential vaccine effectiveness was 47% for the 4-valent vaccine and 70% for the 9-valent vaccine. Within the Cameroonian context, at least one out of five women is likely to be an HR-HPV carrier, especially among young people, smokers, and those with multiple sexual partners. Importantly, HR-HPV infection is highly diversified, with vaccine efficacy ranging from about 47% (4-valent) to 70% (9-valent).