Chapitre 4. Prévention des risques

Introduction Méthodologie La prévention des catastrophes naturelles a d’autant plus d’importance que la confrontation des « systèmes naturels » et des « systèmes humains » génère, et générera de plus en plus compte tenu de l’importance croissante des « systèmes anthropiques » – en particulier urbains -, des enjeux tellement considérables que le développement global des sociétés peut être durablement gêné, voire arrêté pendant de nombreuses années. Les économistes considèrent en effet que, si ..

Chapitre 6. Les systèmes d’information environnementaux

Introduction Un système d’information est un ensemble structuré : de données, de traitements et de leur communication avec leur description à l’aide, respectivement, de structures, de procédures et de protocoles ; de moyens techniques (le système informatique) mais aussi de documents, matériels de reprographie, communication,… ayant pour fonction de générer, mémoriser, traiter, transférer et exploiter des informations dans le cadre d’objectifs définis. Un système d’information repose sur une ..

High SARS-CoV-2 seroprevalence among health care workers in Bamako referral hospitals: a prospective multisite cross-sectional study (ANRS COV11)

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Seroprevalence and risk factors for HIV, HCV, HBV and syphilis among blood donors in Mali

International audienceBACKGROUND:HIV, HBV and HCV remain a global public health concern especially in Africa. Prevalence of these infections is changing and identification of risk factors associated with each infection in Mali is needed to improve medical care.METHODS:We conducted a cross-sectional study of all individuals donating blood (n = 8207) in 2018 to the blood bank at university hospital in Bamako, Mali, to assess prevalence and risks factors associated with HIV, HBV, HCV and syphilis infections.RESULTS:HIV-seroprevalence was 2.16% and significantly increased with age, being married and decreasing education level. In multivariate analysis, after adjustements with age, marital status and geographical setting, only education level was associated with HIV-infection (OR, 1.54 [95% CI, 1.15-2.07], p = 0.016). HBsAg prevalence was 14.78% and significantly increased with to be male gender. In multivariate analysis, adjusting for age, marital status and type of blood donation, education level (OR, 1.17 [95%CI, 1.05-1.31], p = 0.02) and male gender (OR, 1.37 [95%CI, 1.14-1.65], p = 0.005) were associated with HBV-infection. HCV-prevalence was 2.32% and significantly increased with living outside Bamako. In multivariate analysis, adjusting for gender, age and education level, living outside Bamako was associated with HCV-infection (OR, 1.83 [95% CI, 1.41-2.35], p < 0.001). Syphilis seroprevalence was very low (0.04%) with only 3 individuals infected. Contrary to a prior study, blood donation type was not, after adjustments, an independent risk factor for each infection.CONCLUSIONS:Overall, HIV and HBV infection was higher in individuals with a lower level of education, HBV infection was higher in men, and HCV infection was higher in people living outside of Bamako. Compared to studies performed in 1999, 2002 and 2007 in the same population, we found that HIV and HCV prevalence have decreased in the last two decades whereas HBV prevalence has remained stable. Our finding will help guide infection prevention and treatment programs in Mali

Characterization of Drug Resistance and the Defective HIV Reservoir in Virally Suppressed Vertically Infected Children in Mali

Abstract Background In the perspective of ART-free HIV remission, vertically infected children treated with suppressive ART from early infancy represent an optimal population model to better understand the genetic complexity of the reservoir. Objectives To evaluate the proportion of defective viral population and the genotypic resistance patterns in cell-associated HIV DNA. Methods In a cohort including 93 ART-treated vertically HIV-infected (VHIV) children in Mali with plasma HIV-1 RNA ≤q50\,copies/mL for at least 6\,months, we studied total HIV DNA, percentage of defective genomes and resistance by reverse transcriptase and protease bulk sequencing from whole blood in dried blood spots. Results Children had a median age of 9.9\,years at the time of inclusion (IQR\,=\,7.6\textendash 13.4) and 3.3\,years (IQR\,=\,2\textendash 7) at ART initiation; median ART duration was 5.5\,years (IQR\,=\,3.7\textendash 7.3). The median level of total HIV DNA was 470\,copies/106\,cells with one patient presenting undetectable HIV DNA (&lt;66\,copies/106\,cells). We observed the presence of at least one stop codon in viruses from 34 patients (37%). The presence of stop codons was not correlated with the level of HIV DNA or duration of ART. We showed a high prevalence of HIV-1 resistance in DNA with 26% of children harbouring virus resistant to at least one NRTI and 40% to at least one NNRTI. Conclusions While these VHIV children were successfully treated for a long time, they showed high prevalence of resistance in HIV DNA and a moderate defective HIV reservoir

Qualitative and quantitative HIV antibodies and viral reservoir size characterization in vertically infected children with virological suppression

International audienceBackground: Absence of detectable viraemia after treatment cessation in some vertically HIV-infected (VHIV) children suggests that early initiation of HAART could lead to functional cure.Objectives: We described the factors associated with HIV antibody levels and the viral reservoir size in HAART-treated VHIV children.Methods: Study included 97 VHIV children with virological suppression, in Bamako, Mali. The anti-gp41 antibody activities and HIV serostatus were assessed. The viral reservoir size was measured by quantifying total cell-associated HIV DNA.Results: Among the children studied, the median total HIV DNA level was 445 copies/106 cells (IQR = 187–914) and the median anti-gp41 antibody activity was 0.29 OD (IQR = 0.18–0.75). Low activity of anti-gp41 antibodies was associated with a younger age of HAART initiation (P = 0.01). Overall, eight HIV-1 seroreversions were identified.Conclusions: Study identified potential candidates with low viral reservoir and low antibody levels or activities for future trials aiming to reduce HIV-1 reservoir to limit HAART duration

Avenir du fleuve Niger

Le fleuve Niger constitue un véritable poumon humide pour l’Afrique de l’Ouest et plus spécialement pour la république du Mali. Dans ce pays, la gestion du fleuve constitue un enjeu majeur car on y trouve à la fois de remarquables systèmes de production traditionnels associés au phénomène naturel de crue – sources de moyens d’existence pour des centaines de milliers de personnes – mais aussi de grandes réalisations et promesses en matière d’aménagements modernes, hydroélectriques et hydroagricoles. À l’heure où de nouveaux projets d’équipement arrivent à concrétisation et où d’autres sont annoncés, il est important de faire le point sur l’état de santé de ce fleuve et de peser ce qu’il représente pour ses multiples usagers. Cette expertise collégiale, conduite par l’IRD et l’IER et réalisée avec le soutien de plusieurs institutions d’aide au développement et de défense de l’environnement, traite de ces différents aspects avec pour objectif, d’une part, la clarification des cadres institutionnels et des options de politiques publiques et, d’autre part, le renforcement des outils de suivi et d’aide à la décision.The Niger river is truly the main source of life for Western Africa, more specifically for the Republic of Mali. In the country, management of the river is a key topic, as one can find at the same time remarkable traditional production systems associated with the floods which supply hundreds thousands of people – but also great projects which promise modern installations, hydroelectrical and hydroagricultural systems. As new projects come to their end and others begin, it seems important to make a point regarding the health of the river and to evaluate what it represents for its diverse users, civil society or for the economy of Mali. This is the aim of this expert group review, led by the IRD and the IER, with the support of different development and nature protection institutes. Complementarities as well as oppositions that appear from the interactions between the river’s users are described. For the decision-makers in charge of those problems, different recommendations are made, aiming on one hand to clarify institutional frameworks and policy options, and on the other hand to reinforce management and decision-making tools

Prevalence of HIV-1 Natural Polymorphisms and Integrase-Resistance-Associated Mutations in African Children

Integrase inhibitors (INIs) are a potent option for HIV treatment. Limited data exist on INI resistance in West Africa, particularly in children living with HIV/AIDS. We determined the prevalence of integrase gene polymorphisms and the frequency of naturally occurring amino acid (aa) substitutions at positions associated with INI resistance. Dried blood spot (DBS) samples were obtained from one hundred and seven (107) HIV-1-infected children aged less than 15 years old in two West African countries, Benin and Mali. All children were naïve to INI treatment, 56 were naïve to anti-retroviral therapy (ART), and 51 had received ART. Genetic sequencing of HIV integrase was successful in 75 samples. The aa changes at integrase positions associated with INI resistance were examined according to the Stanford HIV Genotypic Resistance database. The median ages were 2.6 and 10 years for ART-naïve and -treated children, respectively. The most common subtypes observed were CRF02_AG (74.7%) followed by CRF06_cpx (20%). No major INI-resistance mutations at positions 66, 92, 121, 143, 147, 148, 155, and 263 were detected. The most prevalent INI accessory resistance mutations were: L74I/M (14/75, 18.6%) followed by E157Q (8/75, 10.6%), G163E/N/T/Q (5/75, 6.6%), Q95A/H/P (2/75, 2.6%), and T97A (4/75, 5.3%). Other substitutions observed were M50I/L/P, H51E/P/S/Q, I72V, T112V, V201I, and T206S. Polymorphisms at positions which may influence the genetic barrier and/or drive the selection of specific INI-resistance pathways were detected. However, no transmitted drug resistance (TDR) to INI was detected among samples of INI-naïve patients. These findings support the use of this treatment class for children with HIV-1, particularly in West Africa