Diagnostic couplé des virus grippaux et du SARS-CoV-2 : évaluation de 2 tests moléculaires

Introduction

Matériels et méthodes

Résultats

Conclusion

Multi-Actors' Co-Implementation of Climate-Smart Village Approach in West Africa: Achievements and Lessons Learnt

Climate change and variability are significant challenges for the environment and food security worldwide. Development strategies focusing simultaneously on adaptive farming, productivity, and reducing greenhouse gas (GHG) emissions-known as climate-smart agriculture (CSA) strategies-are key to responding to these challenges. For almost a decade, within the framework of Climate Change, Agriculture and Food Security (CCAFS), World Agroforestry (ICRAF), and its partners have been using Participatory Action Research (PAR) to fully engage key stakeholders in co-creating such CSA development strategies. This includes the testing of Agricultural Research for Development (AR4D) CSA scalability options. The multidisciplinary teams include the National Research and Extension Systems (NARES), national meteorological services (NMS), non-profit organizations (NGOs), and local radio programs, among others. The CCAFS-West Africa Program, World Agroforestry-West and Central Africa (ICRAF-WCA), International Union for Conservation of Nature (IUCN), University of Reading, and Centre Régional de Formation et d'Application en Agro-météorologie et Hydrologie Opérationnelle (AGRHYMET) provide technical backstopping to the national teams. Climate information (CI) was used as an entry point to inform the development of CSA technologies and practices within Climate-Smart Villages (CSV). This groundwork has led to a greater understanding of three critical factors for successful CSV implementation: (1) Building strong partnerships to co-design and develop agricultural systems that improve ecosystem and population resilience, (2) Key stakeholders (researchers, farmers, development agents, and students) capacity strengthening through vocational and academic training, and (3) Using CI for livelihood planning at all scales. These three factors support more effective identification and testing of agricultural technologies and practices addressing climate variability and change at plot, community, and landscape levels. This paper discusses the PAR-CSA methodology and parameters for evaluation, including biophysical and social change. Keys to success, including communication, knowledge sharing tools, and scalability are also discussed. Finally, future opportunities for improvement are presented, including knowledge product development, CSA policy and investment planning, capacity building, further engagement of the private sector, and additional research on existing practices and tools.

Impact of a malaria intervention package in schools on Plasmodium infection, anaemia and cognitive function in schoolchildren in Mali: a pragmatic cluster-randomised trial

Background

School-aged children are rarely targeted by malaria control programmes, yet the prevalence of Plasmodium infection in primary school children often exceeds that seen in younger children and could affect haemoglobin concentration and school performance.

Methods

A cluster-randomised trial was carried out in 80 primary schools in southern Mali to evaluate the impact of a school-based malaria intervention package. Intervention schools received two interventions sequentially: (1) teacher-led participatory malaria prevention education, combined with distribution of long-lasting insecticidal nets (LLINs), followed 7 months later at the end of the transmission season by (2) mass delivery of artesunate and sulfadoxine-pyrimethamine administered by teachers, termed intermittent parasite clearance in schools (IPCs). Control schools received LLINs as part of the national universal net distribution programme. The impact of the interventions on malaria and anaemia was evaluated over 20 months using cross-sectional surveys in a random subset of 38 schools(all classes), with a range of cognitive measures (sustained attention, visual search, numeracy, vocabulary and writing) assessed in a longitudinal cohort of children aged 9–12 years in all 80 schools.

Results

Delivery of a single round of IPCs was associated with dramatic reductions in malaria parasitaemia (OR 0.005, 95% CI 0.002 to 0.011, p<0.001) and gametocyte carriage (OR 0.02, 95% CI 0.00 to 0.17, p<0.001) in intervention compared with control schools. This effect was sustained for 6 months until the beginning of the next transmission season. IPCs was also associated with a significant decrease in anaemia (OR 0.56, 95% CI 0.40 to 0.78, p=0.001), and increase in sustained attention (difference +0.23, 95% CI 0.10 to 0.36, p<0.001). There was no evidence of impact on other cognitive measures.

Conclusion

The combination of malaria prevention education, LLINs and IPCs can reduce anaemia and improve sustained attention of school children in areas of highly seasonal transmission. These findings highlight the impact of asymptomatic malaria infection on cognitive performance in schoolchildren and the benefit of IPCs in reducing this burden. Additionally, malaria control in schools can help diminish the infectious reservoir that sustains Plasmodium transmission.

Intracellular adhesion molecule-1 up-regulation on thyrocytes by iodine of non-obese diabetic.H2(h4) mice is reactive oxygen species-dependent

Intracellular adhesion molecule-1 (ICAM-1) expression on the thyroid follicular cells of non-obese diabetic (NOD).H2(h4) mice is enhanced by iodide treatment, which correlates with autoimmune thyroid disease in genetically susceptible NOD.H2(h4) mice. The current study examines the mechanism of iodine-enhanced up-regulation of ICAM-1 on the surface of thyroid cells. We hypothesized that the up-regulation of ICAM-1 is due to a transient increase in production of reactive oxygen species (ROS). ROS may initiate signalling of the ICAM-1 gene promoter, enhancing up-regulated ICAM-1 protein on the cell surface. Single-cell suspensions of thyroid follicular cells from thyroiditis-susceptible NOD.H2(h4) or non-susceptible BALB/c mice were treated in vitro with sodium iodide. Extracellular and intracellular ROS were assessed by luminol-derived chemiluminescence and flow cytometry assays respectively. Our results demonstrate that thyroid follicular cells of NOD.H2(h4) generate higher levels of ROS compared with cells from non-susceptible strains of mice. Expression of a subunit protein of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, p67(phox), was analysed by Western blot immunoassay. A constitutive expression of the p67(phox) subunit protein was observed in NOD.H2(h4) mice prior to iodine treatment. No such expression was found in BALB/c mice. Treatment of NOD.H2(h4) thyroid cells with diphenyleneiodium, an inhibitor of NADPH oxidase, reduced generation of ROS and of ICAM-1 protein expression. Thus, thyrocytes from NOD.H2(h4) mice produce enhanced levels of ROS that may be mediated by NADPH oxidase. Consequently, in NOD.H2(h4) mice the ROS-induced signal for ICAM-1 up-regulation may contribute to mononuclear cellular infiltration of the thyroid gland and the progression of autoimmune thyroid disease.

Hemoglobinopathies in the Dogon Country: presence of beta S, beta C, and delta A' genes

The population of the Dogon, located in Mali, is divided in an endogamic Noble class and two endogamic servant castes (Tanners and Blacksmiths). We find that the polymorphic frequencies of beta c, beta S, and, unexpectedly, a mutation of the delta-chain (delta A'), are geographically (valley vs. plateau) as well as social status dependent.

Effects of permethrin as Simulium larvicide on non-target aquatic fauna in an African river

: The side-effects of permethrin (20% EC) as a Simulium larvicide on aquatic invertebrates and fish was studied under operational vector control conditions to contribute to the evaluation of the product for its possible adoption by the Onchocerciasis Control Programme in West Africa. After 15 weekly applications of the formulation at 0.045 litre per m(3) of water discharge, drift samples virtually contained no Ephemeroptera. Saxicolous fauna density and proportional diversity were also affected. However, both drift and saxicolous fauna recovered to almost pretreatment levels a month after treatment was terminated. Fish showed some evidence of stress but remained in the active treated zone to make trends of catches in the area comparable with those of the control station. The treatment did not result in fish mortalities, and the condition of fish before and after the experimental period was significantly unchanged. Thus, operational use of permethrin by the Programme would not be expected to have permanent adverse effects on the non-target fauna.