Advanced in immunological monitoring of HIV infection: profile of immune cells and cytokines in people living with HIV-1 in Benin.

BACKGROUND: Immune cells and cytokines have been linked to viremia dynamic and immune status during HIV infection. They may serve as useful biomarkers in the monitoring of people living with HIV-1 (PLHIV-1). The present work was aimed to assess whether cytokines and immune cell profiles may help in the therapeutic follow-up of PLHIV-1. METHODS: Forty PLHIV-1 in treatment success (PLHIV-1s) and fifty PLHIV-1 in treatment failure (PLHIV-1f) followed at the University Hospital of Abomey-Calavi/Sô-Ava in Benin were enrolled. Twenty healthy persons were also recruited as control group. Circulating cytokines and immune cells were quantified respectively by ELISA and flow cytometry. RESULTS: PLHIV-1 exhibited low proportions of CD4 + T cells, NK, NKT, granulocytes, classical and non-classical monocytes, and high proportions of CD8 + T cells, particularly in the PLHIV-1f group, compared to control subjects. Eosinophils, neutrophils and B cell frequencies did not change between the study groups. Circulating IFN-γ decreased whereas IL-4 significantly increased in PLHIV-1s compared to PLHIV-1f and control subjects even though the HIV infection in PLHIV-1s downregulated the high Th1 phenotype observed in control subjects. However, Th1/Th2 ratio remained biased to a Th1 phenotype in PLHIV-1f, suggesting that high viral load may have maintained a potential pro-inflammatory status in these patients. Data on inflammatory cytokines showed that IL-6 and TNF-α concentrations were significantly higher in PLHIV-1s and PLHIV-1f groups than in control subjects. Significant high levels of IL-5 and IL-7 were observed in PLHIV-1f compared to controls whereas PLHIV-1s presented only a high level of IL-5. No change was observed in IL-13 levels between the study groups. CONCLUSION: Our study shows that, in addition to CD4/CD8 T cell ratio, NK and NKT cells along with IL-6, TNF-α, IL-5 and IL-7 cytokines could serve as valuable immunological biomarkers in the therapeutic monitoring of PLHIV-1 although a larger number of patients would be necessary to confirm these results.

Knowledge, awareness, and risk practices related to bacterial contamination of antiseptics, disinfectants, and hand hygiene products among healthcare workers in sub-saharan Africa: a cross-sectional survey in three tertiary care hospitals (Benin, Burkina Faso, and DR Congo).

BACKGROUND: Antiseptics, disinfectants, and hand hygiene products can be contaminated with bacteria and cause healthcare-associated infections, which are underreported from low- and middle-income countries. To better understand the user-related risk factors, we conducted a knowledge, awareness, and practice survey among hospital staff in sub-Saharan Africa. METHODS: Self-administered questionnaire distributed among healthcare workers in three tertiary care hospitals (Burkina Faso, Benin, Democratic Republic of the Congo). RESULTS: 617 healthcare workers (85.3% (para)medical and 14.7% auxiliary staff) participated. Less than half (45.5%) had been trained in Infection Prevention & Control (IPC), and only 15.7% were trained < 1 year ago. Near two-thirds (64.2%) preferred liquid soap for hand hygiene, versus 33.1% for alcohol-based hand rub (ABHR). Most (58.3%) expressed confidence in the locally available products. Knowledge of product categories, storage conditions and shelf-life was inadequate: eosin was considered as an antiseptic (47.5% of (para)medical staff), the shelf life and storage conditions (non-transparent container) of freshly prepared chlorine 0.5% were known by only 42.6% and 34.8% of participants, respectively. Approximately one-third of participants approved using tap water for preparation of chlorine 0.5% and liquid soap. Most participants (> 80%) disapproved recycling soft-drink bottles as liquid soap containers. Nearly two-thirds (65.0%) declared that bacteria may be resistant to and survive in ABHR, versus 51.0% and 37.4% for povidone iodine and chlorine 0.5%, respectively. Depicted risk practices (n = 4) were ignored by 30 to 40% of participants: they included touching the rim or content of stock containers with compresses or small containers, storing of cotton balls soaked in an antiseptic, and hand-touching the spout of pump dispenser. Filling containers by topping-up was considered good practice by 18.3% of participants. Half (52.1%) of participants acknowledged indefinite reuse of containers. Besides small differences, the findings were similar across the study sites and professional groups. Among IPC-trained staff, proportions recognizing all 4 risk practices were higher compared to non-trained staff (35.9% versus 23.8%, p < 0.0001). CONCLUSIONS: The present findings can guide tailored training and IPC implementation at the healthcare facility and national levels, and sensitize stakeholders' and funders' interest.

Transcriptomic analysis of Anopheles gambiae from Benin reveals overexpression of salivary and cuticular proteins associated with cross-resistance to pyrethroids and organophosphates.

BACKGROUND: Insecticide resistance (IR) is one of the major threats to malaria vector control programs in endemic countries. However, the mechanisms underlying IR are poorly understood. Thus, investigating gene expression patterns related to IR can offer important insights into the molecular basis of IR in mosquitoes. In this study, RNA-Seq was used to characterize gene expression in Anopheles gambiae surviving exposure to pyrethroids (deltamethrin, alphacypermethrin) and an organophosphate (pirimiphos-methyl). RESULTS: Larvae of An. gambiae s.s. collected from Bassila and Djougou in Benin were reared to adulthood and phenotyped for IR using a modified CDC intensity bottle bioassay. The results showed that mosquitoes from Djougou were more resistant to pyrethroids (5X deltamethrin: 51.7% mortality; 2X alphacypermethrin: 47.4%) than Bassila (1X deltamethrin: 70.7%; 1X alphacypermethrin: 77.7%), while the latter were more resistant to pirimiphos-methyl (1.5X: 48.3% in Bassila and 1X: 21.5% in Djougou). RNA-seq was then conducted on resistant mosquitoes, non-exposed mosquitoes from the same locations and the laboratory-susceptible An. gambiae s.s. Kisumu strain. The results showed overexpression of detoxification genes, including cytochrome P450s (CYP12F2, CYP12F3, CYP4H15, CYP4H17, CYP6Z3, CYP9K1, CYP4G16, and CYP4D17), carboxylesterase genes (COEJHE5E, COE22933) and glutathione S-transferases (GSTE2 and GSTMS3) in all three resistant mosquito groups analyzed. Genes encoding cuticular proteins (CPR130, CPR10, CPR15, CPR16, CPR127, CPAP3-C, CPAP3-B, and CPR76) were also overexpressed in all the resistant groups, indicating their potential role in cross resistance in An. gambiae. Salivary gland protein genes related to 'salivary cysteine-rich peptide' and 'salivary secreted mucin 3' were also over-expressed and shared across all resistant groups. CONCLUSION: Our results suggest that in addition to metabolic enzymes, cuticular and salivary gland proteins could play an important role in cross-resistance to multiple classes of insecticides in Benin. These genes warrant further investigation to validate their functional role in An. gambiae resistance to insecticides.

Internet addiction, new contemporary reality in Benin: exploratory analysis of associated factors among medical and paramedical students in 2022 / L'addiction à internet, une réalité contemporaine au Bénin : analyse exploratoire des facteurs associés chez des étudiants du secteur médical et paramédical en 2022.

INTRODUCTION: Nowadays, Internet addiction is a major concern due to the growing number of Internet users and the consequences associated with this addiction. PURPOSE OF THE RESEARCH: In this study, we aimed to determine the prevalence of and factors associated with Internet addiction among health sciences students at the University of Abomey-Calavi. METHODS: A cross-sectional study was conducted among 346 students from the Faculty of Health Sciences and the National Institute of Medical and Health Sciences at the University of Abomey-Calavi. Participants were selected using simple random sampling. Internet addiction was assessed using K. Young's "Internet Addiction Test." Logistic regression modeling was employed to explore factors associated with Internet addiction. The strength of the association was assessed using odds ratios; the confidence interval (CI) was 95%; and a p-value < 0.05 in the final model was considered significant. RESULTS: The prevalence of Internet addiction was 31.8% (95% CI: [23.26% - 41.38%]). Factors associated with Internet addiction were the participant's field of study, poor relationships with friends and family, communication difficulties, depression, and psychoactive substance consumption. CONCLUSIONS: Evidence of Internet addiction exists among students in health sciences institutions in Benin. These findings can support the development of prevention and intervention strategies centered on addressing a public health issue that is still insufficiently recognized.

Introduction: De nos jours, l'addiction à Internet est une préoccupation majeure en raison de l'évolution croissante du nombre d'internautes mais aussi de ses conséquences. But de l'étude: Dans cette étude, nous avons déterminé la prévalence et les facteurs associés à l'addiction à Internet chez les étudiants des sciences de la santé de l'Université d'Abomey-Calavi. Méthodes: Il s'agit d'une étude transversale menée auprès de 346 étudiants de la Faculté des sciences de la santé et de l'Institut national médico-sanitaire de l'Université d'Abomey-Calavi. Ces derniers ont été sélectionnés par échantillonnage aléatoire simple. L'addiction à Internet a été mesurée grâce à l'outil « Internet addiction test de Young ¼. Une modélisation par régression logistique a été utilisée pour explorer les facteurs associés à l'addiction à Internet. La force de l'association a été évaluée avec un rapport de cotes et son intervalle de confiance (IC) à 95 % ; une valeur p <0,05 dans le modèle final a été considérée comme significative. Résultats: La prévalence de l'addiction à Internet était de 31,8 % (IC95 % : [23,26 % - 41,38 %]). La filière d'études, les mauvaises relations avec les proches, les difficultés de communication, la dépression et la consommation de substances psychoactives étaient associées à l'addiction à Internet. Conclusions: Il existe des évidences qui montrent l'addiction à Internet des étudiants des institutions universitaires de santé au Benin. Ces évidences peuvent soutenir la mise en place de stratégies de prévention et de prise en charge axées sur la communication autour d'un phénomène encore insuffisamment perçu comme le problème de santé publique qu'il constitue.

The prevalence and demographic associations of headache in the adult population of Benin: a cross-sectional population-based study.

BACKGROUND: The Global Burden of Disease (GBD) study is increasingly well informed with regard to headache disorders, but sub-Saharan Africa (SSA) remains one of the large regions of the world with limited data directly derived from population-based studies. The Global Campaign against Headache has conducted three studies in this region: Ethiopia in the east, Zambia in the south and Cameroon in Central SSA. Here we report a similar study in Benin, the first from West SSA. METHODS: We used the same methods and questionnaire, applying cluster-randomized sampling in three regions of the country, randomly selecting households in each region, visiting these unannounced and randomly selecting one adult member (aged 18-65 years) of each household. The HARDSHIP structured questionnaire, translated into Central African French, was administered face-to-face by trained interviewers. Demographic enquiry was followed by diagnostic questions based on ICHD-3 criteria. RESULTS: From 2,550 households with eligible members, we recruited 2,400 participants (participating proportion 94.1%). Headache ever was reported by almost all (95.2%), this being the lifetime prevalence. Headache in the last year was reported by 74.9%. Age-, gender- and habitation-adjusted estimates of 1-year prevalence were 72.9% for all headache, 21.2% for migraine (including definite and probable), 43.1% for TTH (also including definite and probable), 4.5% for probable medication-overuse (pMOH) and 3.1% for other headache on ≥ 15 days/month. One-day (point) prevalence of headache was 14.8% according to reported headache on the day preceding interview. CONCLUSIONS: Overall, these findings are evidence that headache disorders are very common in Benin, a low-income country. The prevalence of pMOH, well above the estimated global mean of 1-2%, is evidence that poverty is not a bar to medication overuse. The findings are very much the same as those in a similar study in its near neighbour, Cameroon. With regard to migraine, they are reasonably in accord with two of three earlier studies in selected Beninese populations, which did not take account of probable migraine. This study adds to the hitherto limited knowledge of headache in SSA.

Implementation of post-discharge malaria chemoprevention (PDMC) in Benin, Kenya, Malawi, and Uganda: stakeholder engagement meeting report.

A Stakeholder engagement meeting on the implementation of post-discharge malaria chemoprevention (PDMC) in Benin, Kenya, Malawi, and Uganda was held in Nairobi, Kenya, on 27 September 2023. Representatives from the respective National Malaria Control Programmes, the World Health Organization (WHO) Geneva, Africa Regional and Kenya offices, research partners, non-governmental organizations, and the Medicines for Malaria Venture participated. PDMC was recommended by the WHO in June 2022 and involves provision of a full anti-malarial treatment course at regular intervals during the post-discharge period in children hospitalized with severe anaemia in areas of moderate-to-high malaria transmission. The WHO recommendation followed evidence from a meta-analysis of three clinical trials and from acceptability, delivery, cost-effectiveness, and modelling studies. The trials were conducted in The Gambia using monthly sulfadoxine-pyrimethamine during the transmission season, in Malawi using monthly artemether-lumefantrine, and in Kenya and Uganda using monthly dihydroartemisinin-piperaquine, showing a significant reduction in all-cause mortality by 77% (95% CI 30-98) and a 55% (95% CI 44-64) reduction in all-cause hospital readmissions 6 months post-discharge. The recommendation has not yet been implemented in sub-Saharan Africa. There is no established platform for PDMC delivery. The objectives of the meeting were for the participating countries to share country contexts, plans and experiences regarding the adoption and implementation of PDMC and to explore potential delivery platforms in each setting. The meeting served as the beginning of stakeholder engagement within the PDMC Saves Lives project and will be followed by formative and implementation research to evaluate alternative delivery strategies in selected countries. Meeting highlights included country consensus on use of dihydroartemisinin-piperaquine for PDMC and expansion of the target group to "severe anaemia or severe malaria", in addition to identifying country-specific options for PDMC delivery for evaluation in implementation research. Further exploration is needed on whether the age group should be extended to school-age children.

Application of advanced very high-resolution radiometer (AVHRR)-based vegetation health indices for modelling and predicting malaria in Northern Benin, West Africa.

BACKGROUND: Vegetation health (VH) is a powerful characteristic for forecasting malaria incidence in regions where the disease is prevalent. This study aims to determine how vegetation health affects the prevalence of malaria and create seasonal weather forecasts using NOAA/AVHRR environmental satellite data that can be substituted for malaria epidemic forecasts. METHODS: Weekly advanced very high-resolution radiometer (AVHRR) data were retrieved from the NOAA satellite website from 2009 to 2021. The monthly number of malaria cases was collected from the Ministry of Health of Benin from 2009 to 2021 and matched with AVHRR data. Pearson correlation was calculated to investigate the impact of vegetation health on malaria transmission. Ordinary least squares (OLS), support vector machine (SVM) and principal component regression (PCR) were applied to forecast the monthly number of cases of malaria in Northern Benin. A random sample of proposed models was used to assess accuracy and bias. RESULTS: Estimates place the annual percentage rise in malaria cases at 9.07% over 2009-2021 period. Moisture (VCI) for weeks 19-21 predicts 75% of the number of malaria cases in the month of the start of high mosquito activities. Soil temperature (TCI) and vegetation health index (VHI) predicted one month earlier than the start of mosquito activities through transmission, 78% of monthly malaria incidence. CONCLUSIONS: SVM model D is more effective than OLS model A in the prediction of malaria incidence in Northern Benin. These models are a very useful tool for stakeholders looking to lessen the impact of malaria in Benin.

First report of natural infection of Anopheles gambiae s.s. and Anopheles coluzzii by Wolbachia and Microsporidia in Benin: a cross-sectional study.

BACKGROUND: Recently, bacterial endosymbiont, including Wolbachia and Microsporidia were found to limit the infection of Anopheles mosquitoes with Plasmodium falciparum. This study aimed to investigate the natural presence of key transmission-blocking endosymbionts in Anopheles gambiae and Anopheles coluzzii in Southern Benin. METHODS: The present study was conducted in seven communes (Cotonou, Porto-Novo, Aguégués, Ifangni, Pobè Athiémé, and Grand-Popo) of Southern Benin. Anopheles were collected using indoor/outdoor Human Landing Catches (HLCs) and Pyrethrum Spray Catches (PSCs). Following morphological identification, PCR was used to identify An. gambiae sensu lato (s.l.) to species level and to screen for the presence of both Wolbachia and Microsporidia. Plasmodium falciparum sporozoite infection was also assessed using ELISA. RESULTS: Overall, species composition in An. gambiae s.l. was 53.7% An. coluzzii, while the remainder was An. gambiae sensu stricto (s.s.). Combined data of the two sampling techniques revealed a mean infection prevalence with Wolbachia of 5.1% (95% CI 0.90-18.6) and 1.3% (95% CI 0.07-7.8) in An. gambiae s.s. and An. coluzzii, respectively. The mean infection prevalence with Microsporidia was 41.0% (95% CI 25.9-57.8) for An. gambiae s.s. and 57.0% (95% CI 45.4-67.9) for An. coluzzii. Wolbachia was only observed in Ifangni, Pobè, and Cotonou, while Microsporidia was detected in all study communes. Aggregated data for HLCs and PSCs showed a sporozoite rate (SR) of 0.80% (95% CI 0.09-2.87) and 0.69% (95% CI 0.09-2.87) for An. gambiae and An. coluzzii, respectively, with a mean of 0.74% (95% CI 0.20-1.90). Of the four individual mosquitoes which harboured P. falciparum, none were also infected with Wolbachia and one contained Microsporidia. CONCLUSIONS: The present study is the first report of natural infections of field-collected An. gambiae s.l. populations from Benin with Wolbachia and Microsporidia. Sustained efforts should be made to widen the spectrum of bacteria identified in mosquitoes, with the potential to develop endosymbiont-based control tools; such interventions could be the game-changer in the control of malaria and arboviral disease transmission.

Seroprevalence and renal carriage of pathogenic Leptospira in livestock in Cotonou, Benin.

BACKGROUND: Leptospirosis is a zoonotic disease. It is particularly prevalent in tropical countries and has major consequences for human and animal health. In Benin, the disease's epidemiology remains poorly understood, especially in livestock, for which data are lacking. OBJECTIVES: To characterise Leptospira seroprevalence and locally circulating serogroups in livestock from Cotonou and to estimate the prevalence of Leptospira renal carriage in cattle. METHODS: We conducted a cross-sectional study in February 2020 during which livestock were sampled at an abattoir and in an impoverished city district. We analysed blood samples from 279 livestock animals (i.e. cattle, sheep, goats and pigs) using the microscopic agglutination test. Additionally, samples of renal tissue from 100 cattle underwent 16s rRNA (rrs) real-time PCR analysis. RESULTS: For the 131 cattle, 85 sheep, and 50 goats tested, seroprevalence was 18% (95% confidence interval [CI] [12%, 26%]), 9% (95% CI [4%, 17%] and 2% (95% CI [0%, 9%]), respectively, and most of the seropositive animals were associated with 1:100 titres. All 13 pigs were seronegative. Leptospira DNA was found in the renal tissue of 10% (95% CI [5%, 18%]) of the cattle tested (n = 100). Leptospira borgpetersenii was the main species present (n = 7), but Leptospira interrogans (n = 2) and Leptospira kirschneri (n = 1) were also detected. Various serogroups (Canicola, Grippotyphosa, Sejroe, Icterohaemorrhagiae, Pomona, Pyrogenes, Australis and Autumnalis) were detected using microscopic agglutination test without a clear predominance of any of them. CONCLUSIONS: These results suggest that abattoir workers and people living in close contact with livestock in poor urban areas are exposed to the risk of Leptospira infection.

Work environment and hypertension in industrial settings in Benin in 2019: a cross-sectional study.

OBJECTIVE: To determine the association between occupational factors, particularly psychosocial factors, and hypertension. DESIGN: Descriptive and analytical cross-sectional study using logistic multivariate regression. SETTING: Fifteen cotton ginning plants in Benin. PARTICIPANTS: Permanent and occasional workers in the cotton ginning industry. DATA COLLECTION: Data on sociodemographic, occupational, behavioural and clinical history characteristics were collected using a number of standardised, interviewer-administered questionnaires. These questionnaires were based on the WHO's non-communicable disease questionnaire, Karasek questionnaire and Siegrist questionnaire. Weight, height and blood pressure were measured. Any worker with systolic blood pressure ≥140 mm Hg and/or diastolic blood pressure ≥90 mm Hg according to the WHO criteria was considered hypertensive, as was any subject on antihypertensive treatment even if blood pressure was normal. RESULTS: A total of 1883 workers were included, with a male to female ratio of 9.08. Of these, 510 suffered from hypertension (27.1%, 95% CI 25.1 to 29.2). In the multivariate analysis, the risk factors identified were occupational stress (adjusted OR (aOR)=3.96, 95% CI 1.28 to 12.2), age ≥25 years (aOR=2.77, 95% CI 1.55 to 4.96), body mass index of 25-30 kg/m2 (aOR=1.71, 95% CI 1.32 to 2.2), body mass index >30 kg/m2 (aOR=2.74, 95% CI 1.84 to 4.09), permanent worker status (aOR=1.66, 95% CI 1.44 to 2.41) and seniority in the textile sector >5 years (aOR=2.18, 95% CI 1.7 to 2.8). Recognition at work emerged as an effect-modifying factor subject to stratification. CONCLUSIONS: Occupational factors, particularly job strain and recognition at work, are modifiable factors associated with hypertension in the ginning plants sector and deserve to be corrected through occupational health promotion and prevention.

The frequency of kdr and ace-1 alleles in Anopheles gambiae s.l. before and during indoor residual spraying (IRS) implementation and four years after IRS withdrawal in three districts in Atacora, Benin.

BACKGROUND: Indoor residual spraying (IRS) was first implemented in the Atacora department, Benin from 2011 to 2012 using bendiocarb (carbamate) followed by annual spraying with pirimiphos-methyl (organophosphate) from 2013 to 2018. Before and after IRS implementation in Atacora, standard pyrethroid insecticide-treated bed nets were the main method of vector control in the area. This study investigated the knockdown resistance (kdr) gene (L1014F) and the acetylcholinesterase (ace-1) gene (G119S), before and during IRS implementation, and 4-years after IRS withdrawal from Atacora. This was done to assess how changes in insecticide pressure from indoor residual spraying may have altered the genotypic resistance profile of Anopheles gambiae s.l. METHOD: Identification of sibling species of An. gambiae s.l. and detection of the L1014F mutation in the kdr gene and G119S mutation in ace-1 genes was done using molecular analysis. Allelic and genotypic frequencies were calculated and compared with each other before and during IRS implementation and 4 years after IRS withdrawal. The Hardy-Weinberg equilibrium and genetic differentiation within and between populations were assessed. RESULTS: Prevalence of the L1014F mutation in all geographic An. gambiae s.l. (An. gambiae s.s., Anopheles. coluzzii, Anopheles. arabiensis, and hybrids of "An. gambiae s.s. and An. coluzzii") populations increased from 69% before IRS to 87% and 90% during and after IRS. The G119S allele frequency during IRS (20%) was significantly higher than before IRS implementation (2%). Four years after IRS withdrawal, allele frequencies returned to similar levels as before IRS (3%). Four years after IRS withdrawal, the populations showed excess heterozygosity at the ace-1 gene and deficit heterozygosity at the kdr gene, whereas both genes had excess heterozygosity before and during IRS (FIS < 0). No genetic differentiation was observed within the populations. CONCLUSIONS: This study shows that the withdrawal of IRS with bendiocarb and pirimiphos-methyl may have slowed down the selection of individual mosquitoes with ace-1 resistance alleles in contrast to populations of An. gambiae s.l. with the L1014F resistance allele of the kdr gene. This may suggest that withdrawing the use of carbamates or organophosphates from IRS or rotating alternative insecticides with different modes of action may slow the development of ace-1 insecticide-resistance mutations. The increase in the prevalence of the L1014F mutation of the kdr gene in the population, despite the cessation of IRS, could be explained by the growing use of pyrethroids and DDT in agriculture and for other domestic use. More observational studies in countries where carbamates or organophosphates are still being used as public health insecticides may provide additional insights into these associations.

Monitoring Aedes populations for arboviruses, Wolbachia, insecticide resistance and its mechanisms in various agroecosystems in Benin.

Aedes mosquitoes are the main vectors of arboviruses in Benin. Cases of dengue have been reported in Benin with all four serotypes of the virus actively circulating in this region. Some agricultural settings are known to harbor Aedes vectors responsible for the transmission of arboviruses. The massive use of certain insecticides in agricultural settings has probably contributed to insecticide resistance in these vectors. In Benin, the susceptibility of arbovirus vectors to insecticides is poorly studied. In addition, the distribution of Wolbachia spp., which is used against some arboviruses is unknown. Moreover, there is limited information regarding the vectors responsible for the transmission of arboviruses in Benin. This present study monitored the species composition, arboviruses, and Wolbachia symbiont status, as well as the phenotypic and molecular insecticide resistance profile of Aedes populations from three agroecosystems in Benin. Aedes species identification was performed morphologically and confirmed using qPCR. (RT)-qPCR assay was applied for monitoring the presence of DENV, CHIKV, ZIKV, and WNV pathogens as well as for naturally occurring Wolbachia symbionts. Insecticide resistance was assessed phenotypically, by permethrin (0.75%) exposure of Adults (F0) using World Health Organization (WHO) bioassay protocols, and at the molecular level, using TaqMan (RT)-qPCR assays for assessing knock-down resistance (kdr) mutations (F1534C, V1016G/I, and S989P) and the expression levels of eight detoxification genes (P450s from the CYP9 and CYP6 families, carboxylesterases and glutathione-S-transferases). Aedes aegypti (Ae. aegypti) mosquitoes were the most abundant (93.9%) in the three agroecosystems studied, followed by Aedes albopictus (Ae. albopictus) mosquitoes (6.1%). No arboviruses were detected in the study's mosquito populations. Naturally occurring Wolbachia symbionts were present in 7 pools out of 15 pools tested. This could influence the effectiveness of vector control strategies based on exogenously introduced Wolbachia, all present in the three agroecosystems. Full susceptibility to permethrin was observed in all tested populations of Ae. albopictus. On the contrary, Ae. aegypti were found to be resistant in all three agroecosystem sites except for banana plantation sites, where full susceptibility was observed. Molecular analysis revealed that individual target site resistance kdr mutations F1534C and V1016G/I were detected in most Ae. aegypti populations. Additionally, double mutant (F1534C + V1016G/I) mosquitoes were found in some populations, and in one case, triple mutant (F1534C + V1016G/I + S989P) mosquitoes were detected. Metabolic resistance, as reflected by overexpression of three P450 genes (CYP6BB2, CYP9J26, and CYP9J32), was also detected in Ae. aegypti mosquitoes. Our study provides information that could be used to strategize future vector control strategies and highlights the importance of continuing vector surveillance. Future studies should assess the effect of piperonyl butoxide (PBO) on metabolic resistance and identify the different strains of Wolbachia spp., to choose the best vector control strategies in Benin.

Phenotypic and morphometric characterization of domestic geese raised in northern Benin.

Documentation on the domestic geese (Anser anser) in Benin is scarce, making it objectively difficult to exploit. Its production depends on small flocks raised by livestock farmers in different areas. The aim of the study was to describe the phenotypic and morphometric characteristics of geese encountered in northern Benin. To this end, a total of 576 adult geese (353 males and 223 females) from 102 farms in 4 agro-ecological zones of northern Benin were evaluated for 11 quantitative and 5 qualitative body traits. There are 6 plumage colors with white (42.01%), white-brown magpie (24.65%) and white-grey magpie (17.19%) as dominant colors. The proportions of white-grey (75%) and multicolored (51.85%) in Far northern zone of Benin (FNZB) were higher (P < 0.05) than those in the cotton zone of northern Benin (CZNB), Food-producing zone of southern Borgou (FZSB) and West-Atacora Zone (WAZ). The red coloring of the tarsi was more dominant in the FZSB (63.09%) and the FZSB (61.79%) (P < 0.05). Orange (57.47%) and yellow (28.82%) colored beaks were dominant but did not vary (P > 0.05) from one agro-ecological zone to another. Quantitative traits such as body length, tarsus length, wing span and thoracic circumference of geese varied (P < 0.05) between 71.34 to73.22 cm, 10.08 to 10.6 cm, 131.95 to 135.42 cm and between 42.07 to 43.86 cm respectively. Males differed significantly from females (P < 0.05) for all morphometric traits. The live weight of geese in the FNZB showed higher values than those of other agro-ecological zones (P ˂ 0.05). In addition, white phenotype geese (3.76 kg) were heavier (P ˂ 0.05) than other phenotypes. All correlations between weight and body measurements of domestic geese were positive, but the correlations between live weight and wing span (r = 0.68) were the strongest. These correlations could be used to assess the live weight of the geese population studied and for selection based on live weight. This study provides a reference for morpho-biometric traits and will be complemented by molecular characterization.

How do plant demographic and ecological traits combined with social dynamics and human traits affect woody plant selection for medicinal uses in Benin (West Africa)?

BACKGROUND: Several hypotheses have been used in ethnobotany to explain the plant's selection criteria by people for their daily needs. Thus, it is important to assess synergy and complementarity among them, especially, those concerning the plant use value, social dynamics and human traits. The study aims to (i) highlight people's socio-economic factors, and plant ecological traits that affect the plant use-availability dynamic (PUD); and (ii) assess the available species diversity effect on ethno-medicinal knowledge diversity in Benin. METHODS: Ethnobotanical interviews were carried out to quantify the importance of local species in different ecological zones of Benin with 590 traditional medicine actors. Vegetation surveys were done to assess species availability within 337 plots of 50 m x 40 m or 60 m x 30 m, depending on the climatic zone, for a total of 61.6 ha, established in 15 forests distributed within the 10 phytodistricts of Benin. The plant use availability hypothesis was quantified as a dynamic link between species use value and availability (PUD). A general and mixed linear models were used to assess the significance of each factor's effect on PUD. Pearson correlation test was applied on Shannon diversity index considering inventoried species in the field and those which were cited by people, for the available species diversity effect on ethno-medicinal knowledge diversity assessment. RESULTS: A hundred and twenty woody medicinal plants, mostly trees (68.33%), were sampled. Growth form and its interaction with phytodistrict have a significant effect (p: 0.005) on PUD. The less available trees were the most used in the phytodistricts 3, 4, 8 and 10. PUD varies significantly according to social factors (p: 0.007). Ethnicity, age and main activity were the most quoted social factors which influenced the PUD. Ethnicity and age have various effects considering the phytodistricts. Moreover, the influence of age changes following the main activity. Plant selection did not solely link to the surrounding diversity (r: - 0.293; p: 0.403). Within some phytodistricts, especially those of 3, 4, 8 and 10, the less available tree species were the most requested. CONCLUSION: It is urgent to reforest vegetation patches in some phytodistricts (3, 4, 8 and 10) of Benin with widely requested and no available species to avoid the extinction of their wild populations. This concerns Cassia sieberiana DC., Anonychium africanum (Guill. & Perr.) C. E.Hughes & G. P. Lewis, Pterocarpus erinaceus Poir., Cola millenii K. Schum., Azadirachta indica A. Juss., Khaya senegalensis (Desr.) A. Juss., Pseudocedrela kotschyi (Schweinf.) Harms, Treculia africana Decne. ex Trécul, Uapaca heudelotii Baill., Vitellaria paradoxa C. F. Gaertn., Kigelia africana (Lam.) Benth. and Newbouldia laevis (P. Beauv.) Seem. ex Bureau.

"Our desire is to make this village intestinal worm free": Identifying determinants of high coverage of community-wide mass drug administration for soil transmitted helminths in Benin, India, and Malawi.

BACKGROUND: Soil-transmitted helminth infections (STH) are associated with substantial morbidity in low-and-middle-income countries, accounting for 2.7 million disability-adjusted life years annually. Current World Health Organization guidelines recommend controlling STH-associated morbidity through periodic deworming of at-risk populations, including children and women of reproductive age (15-49 years). However, there is increasing interest in community-wide mass drug administration (cMDA) which includes deworming adults who serve as infection reservoirs as a method to improve coverage and possibly to interrupt STH transmission. We investigated determinants of cMDA coverage by comparing high-coverage clusters (HCCs) and low-coverage clusters (LCCs) receiving STH cMDA in three countries. METHODS: A convergent mixed-methods design was used to analyze data from HCCs and LCCs in DeWorm3 trial sites in Benin, India, and Malawi following three rounds of cMDA. Qualitative data were collected via 48 community-level focus group discussions. Quantitative data were collected via routine activities nested within the DeWorm3 trial, including annual censuses and coverage surveys. The Consolidated Framework for Implementation Research (CFIR) guided coding, theme development and a rating process to determine the influence of each CFIR construct on cMDA coverage. RESULTS: Of 23 CFIR constructs evaluated, we identified 11 constructs that differentiated between HCCs and LCCs, indicating they are potential drivers of coverage. Determinants differentiating HCC and LCC include participant experiences with previous community-wide programs, communities' perceptions of directly observed therapy (DOT), perceptions about the treatment uptake behaviors of neighbors, and women's agency to make household-level treatment decisions. CONCLUSION: The convergent mixed-methods study identified barriers and facilitators that may be useful to NTD programs to improve cMDA implementation for STH, increase treatment coverage, and contribute to the successful control or elimination of STH. TRIAL REGISTRATION: The parent trial was registered at clinicaltrials.gov (NCT03014167).

Chapitre 2. L'autonomisation des comités nationaux d'éthique de la recherche en Afrique : perspective historique et enjeux actuels.

Since the 60s, and particularly after various scandals in the 90s, national research ethics committees in Africa have established themselves as key players in the field of international clinical research. Notably based on the principle of double ethical review, their existence has historically been aimed at preventing a form of ethical dumping, a temptation that still exists today on the part of some research promoters. While the international framework of “soft” law has favored their emergence and legitimacy, a legal and regulatory framework of “hard” law is also necessary at local level for each national research ethics committee, to ensure its proper functioning and the optimal fulfillment of its missions. The aim of this article is to analyze the similarities and differences between three national ethics committees in Africa, specifically the CNERS of Guinea, the CNERS of Benin and the CNESVS of Côte d’Ivoire, in terms of status, missions, legal or regulatory ground and, more generally, autonomy. This analysis will enable us, on the one hand, to take account of common logistical difficulties and, on the other, to go beyond differences in legal status and missions to define what enables this type of committee to fully exercise its role(s). Finally, this article proposes to model the various elements that contribute to the autonomy and resilience of a national research ethics committee, around a notion proposed on this occasion: the “circles of autonomy”.

Chapitre 3. Inégalités dans le dépistage et la prévention du VIH/SIDA.

Despite progress in the detection and treatment of the Human Immunodeficiency Virus (HIV), major challenges remain in developing countries due to insufficient resources and infrastructure. The number of people living with HIV who do not know their serostatus has fallen worldwide. However, a number of existing obstacles stand in the way of better results. The socio-cultural context in Africa hampers knowledge and understanding of the disease, leading to stigmatizing attitudes, reluctance to undergo screening and poor access to treatment.Inequalities also exist within the countries of the North, as in the case of the French West Indies, which benefit from a policy to combat HIV/AIDS, with results that fall short of those in mainland France. For this reason, we have chosen to compare the situation in the West Indies with that in Benin, in the context of African culture.Our analysis takes stock of the issues and prospects linked to the accessibility and use of screening care in sub-Saharan Africa and the French Departments of America (DFA).In both cases, fear of the disease, stigmatization, fear of a positive HIV test result and fear of disclosing the test result limit preventive and treatment actions for an effective fight against HIV.In sub-Saharan Africa, women are more likely to accept a screening test than men. Certain populations, including adolescents and homosexuals, are in a vulnerable position. The comparison reveals similar attitudes and suggests actions or recommendations in both countries that have produced results.Innovative strategies and specific programs must be implemented to turn the tide in the fight against the HIV epidemic.

Towards an intelligent malaria outbreak warning model based intelligent malaria outbreak warning in the northern part of Benin, West Africa.

BACKGROUND: Malaria is one of the major vector-borne diseases most sensitive to climatic change in West Africa. The prevention and reduction of malaria are very difficult in Benin due to poverty, economic insatiability and the non control of environmental determinants. This study aims to develop an intelligent outbreak malaria early warning model driven by monthly time series climatic variables in the northern part of Benin. METHODS: Climate data from nine rain gauge stations and malaria incidence data from 2009 to 2021 were extracted from the National Meteorological Agency (METEO) and the Ministry of Health of Benin, respectively. Projected relative humidity and temperature were obtained from the coordinated regional downscaling experiment (CORDEX) simulations of the Rossby Centre Regional Atmospheric regional climate model (RCA4). A structural equation model was employed to determine the effects of climatic variables on malaria incidence. We developed an intelligent malaria early warning model to predict the prevalence of malaria using machine learning by applying three machine learning algorithms, including linear regression (LiR), support vector machine (SVM), and negative binomial regression (NBiR). RESULTS: Two ecological factors such as factor 1 (related to average mean relative humidity, average maximum relative humidity, and average maximal temperature) and factor 2 (related to average minimal temperature) affect the incidence of malaria. Support vector machine regression is the best-performing algorithm, predicting 82% of malaria incidence in the northern part of Benin. The projection reveals an increase in malaria incidence under RCP4.5 and RCP8.5 over the studied period. CONCLUSION: These results reveal that the northern part of Benin is at high risk of malaria, and specific malaria control programs are urged to reduce the risk of malaria.

Finding optimum climatic parameters for high tomato yield in Benin (West Africa) using frequent pattern growth algorithm.

Tomato is one of the most appreciated vegetables in the world. Predicting its yield and optimizing its culture is important for global food security. This paper addresses the challenge of finding optimum climatic values for a high tomato yield. The Frequent Pattern Growth (FPG) algorithm was considered to establish the associations between six climate variables: minimum and maximum temperatures, maximum humidity, sunshine (Sun), rainfall, and evapotranspiration (ET), collected over 26 years in the three agro-ecological Zones of Benin. Monthly climate data were aggregated with yield data over the same period. After aggregation, the data were transformed into 'low', 'medium', and 'high' attributes using the threshold values defined. Then, the rules were generated using the minimum support set to 0.2 and the confidence to 0.8. Only the rules with the consequence 'high yield' were screened. The best yield patterns were observed in the Guinean Zone, followed by the Sudanian. The results indicated that high tomato yield was associated with low ET in all areas considered. Minimum and maximum temperatures, maximum humidity, and Sun were medium in every Zone. Moreover, rainfall was high in the Sudanian Zone, unlike the other regions where it remained medium. These results are useful in assessing climate variability's impact on tomato production. Thus, they can help farmers make informed decisions on cultivation practices to optimize production in a changing environment. In addition, the findings of this study can be considered in other regions and adapted to other crops.

[Intradermal and serologic testing for insect bite hypersensitivity in a Dahomey-Ox]. / Intradermaler und serologischer Allergietest zur Abklärung einer Insektenstich-Hypersensitivität bei einem Dahomey-Ochsen.

This case report describes an eosinophilic dermatitis on the prepuce of a Dahomey-Ox caused by an insect bite hypersensitivity against Culicoides spp. To the best of the authors' knowledge, this is the first report describing intradermal allergy and serological testing in cattle.