Michel Carlos TOMMO TCHOUAKET

Mr. Michel Carlos TOMMO TCHOUAKET

orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-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
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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
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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
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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.

19 May 2020 in Virology Journal
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SSSamuel Martin Sosso
Samuel Martin Sosso
MTMichel Carlos TOMMO TCHOUAKET
Michel Carlos TOMMO TCHOUAKET
JFJoseph Fokam
Joseph Fokam
RSRachel Kamgaing Simo
Rachel Kamgaing Simo
JTJudith Torimiro
Judith Torimiro
ANAlexis Ndjolo
Alexis Ndjolo
Background: Human papillomavirus (HPV) is the leading cause of cervical cancers, causing 270.000 deaths annually worldwide of which 85% occur in developing countries with an increasing risk associated to HIV infection. This study aimed at comparing HPV’s positivity and genotype distribution in women according to their HIV status and determinants. Methods: A comparative study was carried out in 2012 at the Chantal BIYA International Reference Centre (CIRCB) among 278 women enrolled consecutively at the General Hospital and the Gynaeco-Obstetric and Paediatric Hospital of the City of Yaoundé. HPV genotyping was performed by real-time PCR, HIV serological screening by serial algorithm, CD4 T cell phenotyping by flow cytometry and HIV viral load by Abbott m2000RT. Statistical analyses were performed using Microsoft Excel 2016 and Graph Pad version 6.0 software; with P < 0.05 considered statistically significant. Results: Globally, mean age was 37 ± 3 years; median CD4-count for HIV+ was 414 cells/mm3 [IQR: 264.75–588] and median viremia was 50 RNA copies/mL [IQR: < 40–8288]. Overall HPV rate was 38.49% (107/278); 58.88% for single women vs. others (28.97% married, 2.80% divorced, 9.34% for widows), OR: 2.164; p = 0.0319. Following HIV status, HPV rate was 43.48% (80/184) among HIV+ vs. 28.72% (27/94) among HIV- (OR: 1.937; p < 0.0142); HPV genotypes among HIV+ vs. HIV- were respectively distributed as follows: genotype 16 (3.75% vs. 0.00%, p = 0.57), genotype 18 (3.75% vs. 3.70%, p = 1.00), co-infection 16 and others (8.75% vs. 7.40%, p = 1.00), co-infection 18 and others (8.75% vs. 11.11%, p = 0.71), co-infection 16, 18 and others (2.50% vs. 0.00%, p = 1.00) and other genotypes (72.50% vs. 77.78%, p = 0.80). Among HIV+ participants, HPV rate following CD4 was 62.88% (61/97) for CD4 < 500 vs. 35.71% (20/56) for CD4 ≥ 500 (OR: 3.05; p = 0.0012) while HPV rate following HIV viremia was 42.71% (41/96) with < 1000 RNA copies/ml vs. 66.00% (33/50) with > 1000 RNA copies/ml (OR = 0.384; p = 0.009). Conclusion: In Yaoundé, HPV rate appear to be very high, with higher rates of genotypes other than 16 and 18. In the event of HIV infection, the risk of HPV positivity is two times higher, favoured essentially by immunodeficiency. Thus, HIV-infected women should be closely monitored to prevent the emergence of cervical cancer.

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).

12 September 2024 in Biomedicines
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JFJoseph Fokam
Joseph Fokam
YBYagai Bouba
Yagai Bouba
RARogers Awoh Ajeh
Rogers Awoh Ajeh
DGDominik Tameza Guebiapsi
Dominik Tameza Guebiapsi
SESuzane Essamba
Suzane Essamba
ABAnne-Cecile Zoung-Kanyi Bissek
Anne-Cecile Zoung-Kanyi Bissek
Mortality in children accounts for 15% of all AIDS-related deaths globally, with a higher burden among Cameroonian children (25%), likely driven by poor virological response. We sought to evaluate viral suppression (VS) and its determinants in a nationally representative paediatric and young adult population receiving antiretroviral therapy (ART). A cross-sectional and multicentric study was conducted among Cameroonian children (<10 years), adolescents (10–19 years) and young adults (20–24 years). Data were collected from the databases of nine reference laboratories from December 2023 to March 2024. A conditional backward stepwise regression model was built to assess the predictors of VS, defined as a viral load (VL) <1000 HIV-RNA copies/mL. Overall, 7558 individuals (females: 73.2%) were analysed. Regarding the ART regimen, 17% of children, 80% of adolescents and 83% of young adults transitioned to dolutegravir (DTG)-based regimens. Overall VS was 82.3%, with 67.3% (<10 years), 80.5% (10–19 years) and 86.5% (20–24 years), and p < 0.001. VS was 85.1% on a DTG-based regimen versus 80.0% on efavirenz/nevirapine and 65.6% on lopinavir/ritonavir or atazanavir/ritonavir. VS was higher in females versus males (85.8% versus 78.2%, p < 0.001). The VS rate remained stable around 85% at 12 and 24 months but dropped to about 80% at 36 months after ART initiation, p < 0.009. Independent predictors of non-VS were younger age, longer ART duration (>36 months), backbone drug (non-TDF/3TC) and anchor drug (non-DTG based). In this Cameroonian paediatric population with varying levels of transition to DTG, overall VS remains below the 95% targets. Predictors of non-VS are younger age, non-TDF/3TC- and non-DTG-based regimens. Thus, efforts toward eliminating paediatric AIDS should prioritise the transition to a DTG-based regimen in this new ART era.