Etude Comparative Des Produits Issus De La Transformation En Filature Des Fibres De Trois Nouvelles Variétés De Cotonnier

Résumé - Au Mali, comme ailleurs en Afrique, la sélection variétale est à la base du succès de la culture cotonnière. Le coton du Mali est presqu’entièrement exporté ; les fibres issues des variétés cultivées doivent répondre aux exigences du marché en termes de caractéristiques technologiques des fibres, facteurs clés du fonctionnement de la filature. Cette étude comparative a été réalisée sur trois nouvelles variétés de cotonniers A, B et C, issues d’un point d'expérimentation. L'objectif de l'étude est d’identifier les variétés ayant les meilleures performances variétales et industrielles pour la vulgarisation en production commerciale par les sociétés cotonnières. 1 échantillon représentatif de 100g de coton fibre, 20 échantillons de 5 m de rubans de carde, d’étirage et de 10 m de mèches, 30 échantillons de 100 m de fil et 40 échantillons de 500 mm de fil ont été respectivement prélevés par balle de chaque variété et à différentes étapes du processus de transformation par variété. Ces échantillons ont été testés sur des appareils de mesure dans les conditions requises au laboratoire de métrologie textile du CERFITEX, Ségou - Mali.L’analyse de variance (ANOVA) des données relatives aux fibres, rubans, mèches et fils et la comparaison de leurs principales caractéristiques de qualité à celle de la production mondiale avec l’application des USTER STATISTICS 2018 ont montré que les variétés de cotonnier A et B sont nettement meilleures que celle de C. Les performances variétales et industrielles de A et B, meilleures que celles de C sont recommandées à la vulgarisation Mots clés : Coton, caractéristiques technologiques, qualité, fibres, fils. [Comparative Study Of The Products Resulting From The Transformation Into Spinning Of The Fibers Of Three New Varieties Of Cotton]Abstract - In Mali, as elsewhere in Africa, varietal selection is the basis of the success of cotton growing. Cotton from Mali is almost entirely exported; fibers from cultivated varieties must meet market requirements in terms of the technological characteristics of fibers, key factors in the operation of the spinning mill. This comparative study was carried out on three new varieties of cotton A, B and C, from an experimental point. The objective of the study is to identify the varieties with the best varietal and industrial performance for popularization in commercial production by cotton companies. 1 representative sample of 100g of cotton fiber, 20 samples of 5m of carding and drawing slivers and 10m of rovings, 30 samples of 100m of yarn and 40 samples of 500mm of yarn were respectively taken per bale of each variety and at different stages of the transformation process by variety. These samples were tested on measuring devices under the required conditions at the CERFITEX textile metrology laboratory, Ségou - Mali.The analysis of variance (ANOVA) of fiber, sliver, roving and yarn data and the comparison of their main quality characteristics to that of world production with the application of USTER STATISTICS 2018 showed that cotton varieties A and B are clearly better than those of C. The varietal and industrial performances of A and B, better than that of C are recommended for popularisation Keywords : Cotton, technological characteristics, quality, fibres, yarns

Concordance of vaccination status and associated factors with incomplete vaccination: a household survey in the health district of Segou, Mali, 2019

Introduction: the region of Segou recorded 36.8% of children were incompletely vaccinated in 2018. In 2019, the district of Segou was one of the districts with the lowest vaccination coverage in the region, with 85.1% coverage for the three doses of the pentavalent vaccine and 85.4% for the measles vaccine. This study was initiated to better understand this low vaccination coverage, in the absence of specific studies on vaccination coverage in the district of Segou. Methods: a prospective cross-sectional study was conducted from May to August 2020 with 30 clusters. We performed Kappa coefficient, bivariate, and multiple logistic regression analysis. Results: findings showed that 18.46% (101/547) [15.44-21.93] of children were incompletely vaccinated. Mothers correctly reported the vaccination status of their children in 67.30% of cases (Kappa coefficient). Uneducated (OR[IC95%]=2.13[1.30-3.50]), living in rural area (OR[IC95%]=2.07[1.23-3.47]), lack of knowledge of Expanded Program on Immunization (EPI) target diseases (OR[IC95%]=2.37[1.52-3.68]), lack of knowledge of vaccination schedule (OR[IC95%]=3.33[1.90-5.81]) and lack of knowledge of the importance of vaccination (OR[IC95%]=3.6[2.35-6.32]) were associated with incomplete vaccination. In multivariate analysis, uneducated (ORa[IC95%>]=1.68[1.004-2.810]) and lack of knowledge of the importance of vaccination were associated with incomplete vaccination (ORa[IC95%]=3.40[2.049-5.649]). Conclusion: findings showed a good concordance of the vaccination status. Living in a rural area, no education, lack of the knowledge of EPI target diseases, lack of the knowledge of vaccination schedule and lack of knowledge of the importance of vaccination were associated with incomplete vaccination

Unexpected Rift Valley Fever Outbreak, Northern Mauritania

During September–October 2010, an unprecedented outbreak of Rift Valley fever was reported in the northern Sahelian region of Mauritania after exceptionally heavy rainfall. Camels probably played a central role in the local amplification of the virus. We describe the main clinical signs (hemorrhagic fever, icterus, and nervous symptoms) observed during the outbreak

First external quality assessment of molecular and serological detection of rift valley fever in the western Mediterranean region

Pas de clé UTRift Valley fever (RVF) is a mosquito-borne viral zoonosis which affects humans and a wide range of domestic and wild ruminants. The large spread of RVF in Africa and its potential to emerge beyond its geographic range requires the development of surveillance strategies to promptly detect the disease outbreaks in order to implement efficient control measures, which could prevent the widespread of the virus to humans. The Animal Health Mediterranean Network (REMESA) linking some Northern African countries as Algeria, Egypt, Libya,Mauritania, Morocco, Tunisia with Southern European ones as France, Italy, Portugal and Spain aims at improving the animal health in the Western Mediterranean Region since 2009. In this context, a first assessment of the diagnostic capacities of the laboratories involved in the RVF surveillance was performed. The first proficiency testing (external quality assessment— EQA) for the detection of the viral genome and antibodies of RVF virus (RVFV) was carried out from October 2013 to February 2014. Ten laboratories participated from 6 different countries (4 from North Africa and 2 from Europe). Six laboratories participated in the ring trial for both viral RNA and antibodies detection methods, while four laboratories participated exclusively in the antibodies detection ring trial. For the EQA targeting the viral RNA detection methods 5 out of 6 laboratories reported 100% of correct results. One laboratory misidentified 2 positive samples as negative and 3 positive samples as doubtful indicating a need for corrective actions. For the EQA targeting IgG and IgM antibodies methods 9 out of the 10 laboratories reported 100% of correct results, whilst one laboratory reported all correct results except one false-positive. These two ring trials provide evidence that most of the participating laboratories are capable to detect RVF antibodies and viral RNA thus recognizing RVF infection in affected ruminants with the diagnostic methods currently available

West Africa International Centers of Excellence for Malaria Research: Drug Resistance Patterns to Artemether-Lumefantrine in Senegal, Mali, and The Gambia.

In 2006, artemether-lumefantrine (AL) became the first-line treatment of uncomplicated malaria in Senegal, Mali, and the Gambia. To monitor its efficacy, between August 2011 and November 2014, children with uncomplicated Plasmodium falciparum malaria were treated with AL and followed up for 42 days. A total of 463 subjects were enrolled in three sites (246 in Senegal, 97 in Mali, and 120 in Gambia). No early treatment failure was observed and malaria infection cleared in all patients by day 3. Polymerase chain reaction (PCR)-adjusted adequate clinical and parasitological response (ACPR) was 100% in Mali, and the Gambia, and 98.8% in Senegal. However, without PCR adjustment, ACPR was 89.4% overall; 91.5% in Mali, 98.8% in Senegal, and 64.3% in the Gambia (the lower value in the Gambia attributed to poor compliance of the full antimalarial course). However, pfmdr1 mutations were prevalent in Senegal and a decrease in parasite sensitivity to artesunate and lumefantrine (as measured by ex vivo drug assay) was observed at all sites. Recrudescent parasites did not show Kelch 13 (K13) mutations and AL remains highly efficacious in these west African sites

A year of genomic surveillance reveals how the SARS-CoV-2 pandemic unfolded in Africa.

The progression of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in Africa has so far been heterogeneous, and the full impact is not yet well understood. In this study, we describe the genomic epidemiology using a dataset of 8746 genomes from 33 African countries and two overseas territories. We show that the epidemics in most countries were initiated by importations predominantly from Europe, which diminished after the early introduction of international travel restrictions. As the pandemic progressed, ongoing transmission in many countries and increasing mobility led to the emergence and spread within the continent of many variants of concern and interest, such as B.1.351, B.1.525, A.23.1, and C.1.1. Although distorted by low sampling numbers and blind spots, the findings highlight that Africa must not be left behind in the global pandemic response, otherwise it could become a source for new variants

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance.

Investment in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing in Africa over the past year has led to a major increase in the number of sequences that have been generated and used to track the pandemic on the continent, a number that now exceeds 100,000 genomes. Our results show an increase in the number of African countries that are able to sequence domestically and highlight that local sequencing enables faster turnaround times and more-regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and illuminate the distinct dispersal dynamics of variants of concern-particularly Alpha, Beta, Delta, and Omicron-on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve while the continent faces many emerging and reemerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Towards the description of livestock mobility in Sahelian Africa: Some results from a survey in Mauritania.

Understanding spatio-temporal patterns of host mobility is a key factor to prevent and control animal and human diseases. This is utterly important in low-income countries, where animal disease epidemics have strong socio-economic impacts. In this article we analyzed a livestock mobility database, whose data have been collected by the Centre National d'Elevage et de Recherches Vétérinaires (CNERV) Mauritania, to describe its patterns and temporal evolution. Data were collected through phone and face-to-face interviews in almost all the regions in Mauritania over a period of roughly two weeks during June 2015. The analysis has shown the existence of two mobility patterns throughout the year: the first related to routine movements from January to August; the second strictly connected to the religious festivity of Tabaski that in 2014 occurred at the beginning of October. These mobility patterns are different in terms of animals involved (fewer cattle and dromedaries are traded around Tabaski), the means of transportation (the volume of animals moved by truck raises around Tabaski) and destinations (most of the animals are traded nationally around Tabaski). Due to the differences between these two periods, public health officers, researchers and other stakeholders should take account of the time of the year when implementing vaccination campaigns or creating surveillance networks

Comprehensive Phylogenetic Reconstructions of Rift Valley Fever Virus: The 2010 Northern Mauritania Outbreak in the Camelus dromedarius Species

International audienceRift valley fever (RVF) is a mosquito-borne disease of domestic and wild ruminants caused by RVF virus (RVFV), a phlebovirus (Bunyaviridae). RVF is widespread in Sub-Saharan Africa. In September of 2010, an RVF outbreak occurred in northern Mauritania involving mass abortions in small ruminants and camels (Camelus dromedarius) and at least 63 human clinical cases, including 13 deaths. In camels, serological prevalence was 27.5-38.5% (95% confidence interval, n=279). For the first time, clinical signs other than abortions were reported in this species, including hemorrhagic septicemia and severe respiratory distress in animals. We assessed the presence of RVFV in camel sera sampled during this outbreak and generated whole-genome sequences of RVFV to determine the possible origin of this RVFV strain. Phylogenetic analyses suggested a shared ancestor between the Mauritania 2010 strain and strains from Zimbabwe (2269, 763, and 2373), Kenya (155_57 and 56IB8), South Africa (Kakamas, SA75 and SA51VanWyck), Uganda (Entebbe), and other strains linked to the 1987 outbreak of RVF in Mauritania (OS1, OS3, OS8, and OS9)