Les aspects parasitologiques de l'épidémiologie du paludisme dans le Sahara malien

Dans le cadre de l'évaluation épidémiologique de la Transsaharienne, une enquête transversale paludométrique a été réalisée d'Août 1988 à Septembre 1988 le long du tronçon malien. Neuf localités ont été visitées : Douentza, Gossi, Bourem, Almoustarat, Anefis, Aguel-Hoc, Tarlit, Tessalit, Kidal, Bouressa. 2185 unités ont été prélevées pour les études cliniques, parasitologiques et immunologiques. L'indice plasmodique global est de 5,3 % avec une grande variation du Sud (44,6 %) au Nord (0 %). L'indice gamétocytique et l'indice splénique sont très faibles. #P. falciparum est l'espèce dominante. #P. malariae a été décrit une fois en association avec #P. falciparum. #P. ovale n'a jamais été observé. Par contre un cas de #P. vivax a été décrit chez une jeune fille leucoderme de 8 ans à Kidal. #A. gambiae s.s. (forme Mopti) et #A. arabiensis sont les principaux vecteurs au Nord du Mali. Une hypothèse de circulation de #P. vivax dans le Sahara malien est émise. (Résumé d'auteur

Evaluation of the antimicrobial susceptibility testing process in clinical microbiology laboratories at Niamey, Niger

Background: Risk assessment is the means of identifying and evaluating potential errors or problems that may occur in testing process. The aim of this study was to perform risk assessment of antimicrobial susceptibility testing (AST) process in clinical microbiology laboratories of Niamey, Niger Republic.Methodology: We conducted a descriptive cross-sectional study from October 1 to December 31, 2019, to evaluate AST performance in seven clinical microbiology laboratories at Niamey, the capital city of Niger republic. The evaluation focused on the determination of the criticality index (CI) of each critical point (frequency of occurrence of anomalies, severity of the process anomaly, and detectability of the anomaly during the process) in the AST process and the performance of the AST through an observation sheet using two reference strains; Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 29213.Results: The criticality index (CI) was greater than 6 for most of the critical points related to material, medium, equipment, method and labour for the AST process in all the laboratories. A range of 18-100% errors on the inhibition zone diameters of the reference strains were observed. Major and/or minor categorization (Sensitive S, Intermediate I and Resistance R) discrepancies were found at all the laboratories for either one or both reference strains. The antibiotics most affected by the S/I/R discrepancies were trimethoprim (100%), vancomycin (100%), amoxicillin (80%) and amoxicillin + clavulanic acid (70%).Conclusion: This study showed a deficiency in the control of critical control points that impacts the performance of the AST reported by the laboratories in Niger. Corrective actions are needed to improve the performance of AST in clinical microbiology laboratories in Niger.   French title: Evaluation du processus de réalisation de l’antibiogramme dans les laboratoires d’analyses de biologie médicale de la ville de Niamey, Niger Contexte: L'évaluation des risques est le moyen d'identifier et d'évaluer les erreurs ou les problèmes potentiels qui peuvent survenir dans le processus de test. L'objectif de cette étude était de réaliser une évaluation des risques du processus d'antibiogramme (ABG) dans les laboratoires de microbiologie clinique de Niamey, en République du Niger.Méthodologie: Nous avons mené une étude transversale descriptive du 1er octobre au 31 décembre 2019 pour évaluer la performance des ABG dans sept laboratoires de microbiologie clinique à Niamey, capitale de la république du Niger. L'évaluation a porté sur la détermination de l'indice de criticité (IC) de chaque point critique (fréquence d'apparition des anomalies, gravité de l'anomalie du processus et détectabilité de l'anomalie au cours du processus) dans le processus et la performance des AGB à travers une fiche d'observation en utilisant deux souches de référence; Escherichia coli ATCC 25922 et Staphylococcus aureus ATCC 29213.Résultats: L'indice de criticité était supérieur à 6 pour la plupart des points critiques liés au matériel, au milieu, à l'équipement, à la méthode et à la main-d'oeuvre pour le processus AST dans tous les laboratoires. Une fourchette d'erreurs de 18 à 100% sur les diamètres des zones d'inhibition des souches de référence a été observée. Des écarts de catégorisation majeurs et/ou mineurs (Sensible: S, Intermédiaire: I et Résistance: R) ont été constatés dans tous les laboratoires pour l'une ou les deux souches de référence. Les  antibiotiques les plus touchés par les écarts S/I/R étaient la triméthoprime (100%), la vancomycine (100%), l'amoxicilline (80%) et l'amoxicilline + acide clavulanique (70%).Conclusion: Cette étude a montré une déficience dans le contrôle des points de contrôle critiques qui a un impact sur la performance de l'antibiogramme rapportée par les laboratoires au Niger. Des actions correctives sont nécessaires pour améliorer la performance des ABG dans les laboratoires de microbiologie clinique au Niger

Further Confirmation of Broadly Conserved, Highly Immunogenic Cross-Clade HIV CTL Epitopes for Inclusion in the GAIA HIV Vaccine

Poster Presentation From AIDS Vaccine 2012 Boston, MA, USA. 9-12 September 201

Uptake of plasmodium falciparum gametocytes during mosquito bloodmeal by direct and membrane feeding

Plasmodium falciparum remains one of the leading causes of child mortality, and nearly half of the world’s population is at risk of contracting malaria. While pathogenesis results from replication of asexual forms in human red blood cells, it is the sexually differentiated forms, gametocytes, which are responsible for the spread of the disease. For transmission to succeed, both mature male and female gametocytes must be taken up by a female Anopheles mosquito during its blood meal for subsequent differentiation into gametes and mating inside the mosquito gut. Observed circulating numbers of gametocytes in the human host are often surprisingly low. A pre-fertilization behavior, such as skin sequestration, has been hypothesized to explain the efficiency of human-to-mosquito transmission but has not been sufficiently tested due to a lack of appropriate tools. In this study, we describe the optimization of a qPCR tool that enables the relative quantification of gametocytes within very small input samples. Such a tool allows for the quantification of gametocytes in different compartments of the host and the vector that could potentially unravel mechanisms that enable highly efficient malaria transmission. We demonstrate the use of our gametocyte quantification method in mosquito blood meals from both direct skin feeding on Plasmodium gametocyte carriers and standard membrane feeding assay. Relative gametocyte abundance was not different between mosquitoes fed through a membrane or directly on the skin suggesting that there is no systematic enrichment of gametocytes picked up in the skin

Knowledge/Attitude/Practices of HPV & Cervical Cancer, Willingness to Participate in Vaccine Trial in Preparation for HIV & HPV Vaccine Trials in Mali

Oral Presentation from AIDS Vaccine 2012 Boston, MA, USA. 9-12 September 201

Different Plasmodium falciparum clearance times in two Malian villages following artesunate monotherapy.

BACKGROUND: Artemisinin resistance described as increased parasite clearance time (PCT) is rare in Africa. More sensitive methods such as qPCR might better characterize the clearance phenotype in sub-Saharan Africa. METHODS: PCT is explored in Mali using light microscopy and qPCR after artesunate for uncomplicated malaria. In two villages, patients were followed for 28 days. Blood smears and spots were collected respectively for microscopy and qPCR. Parasitemia slope half-life was calculated after microscopy. Patient residual parasitemia were measured by qPCR. RESULTS: Uncorrected adequate clinical and parasitological responses (ACPR) observed in Faladje and Bougoula-Hameau were 78% and 92%, respectively (p=0.01). This reached 100% for both after molecular correction. Proportions of 24H microscopy positive patients in Faladje and Bougoula-Hameau were 97.2% and 72%, respectively (p<0.0001). Slope half-life was 2.8h in Faladje vs 2H in Bougoula-Hameau (p<0.001) and Proportions of 72H patients with residual parasitemia were 68.5% and 40% in Faladje and Bougoula-Hameau, respectively (p=0.003). The mean residual parasitemia was 2.9 in Faladje vs. 0.008 in Bougoula-Hameau (p=0.002). Although artesunate is efficacious in Mali, the longer parasite clearance time with submicroscopic parasitemia observed may represent early signs of developing P. falciparum resistance to artemisinins

Low-cost adaptation options to support green growth in agriculture, water resources, and coastal zones

The regional climate as it is now and in the future will put pressure on investments in sub-Saharan Africa in water resource management, fisheries, and other crop and livestock production systems. Changes in oceanic characteristics across the Atlantic Ocean will result in remarkable vulnerability of coastal ecology, littorals, and mangroves in the middle of the twenty-first century and beyond. In line with the countries' objectives of creating a green economy that allows reduced greenhouse gas emissions, improved resource efficiency, and prevention of biodiversity loss, we identify the most pressing needs for adaptation and the best adaptation choices that are also clean and affordable. According to empirical data from the field and customized model simulation designs, the cost of these adaptation measures will likely decrease and benefit sustainable green growth in agriculture, water resource management, and coastal ecosystems, as hydroclimatic hazards such as pluviometric and thermal extremes become more common in West Africa. Most of these adaptation options are local and need to be scaled up and operationalized for sustainable development. Governmental sovereign wealth funds, investments from the private sector, and funding from global climate funds can be used to operationalize these adaptation measures. Effective legislation, knowledge transfer, and pertinent collaborations are necessary for their success