The economic and ecological effects of water management choices in the upper Niger river: Development of decision support methods

One million people in the Inner Niger Delta make a living from arable farming, fisheries and livestock. Upstream dams (one built for electricity generation and one for irrigation) affect this downstream multifunctional use of water. Additionally, the Inner Niger Delta, which is one of the largest Ramsar sites in the world, is a hotspot of biodiversity and accommodates two of the largest known breeding colonies of large wading birds in Africa and in addition, is a vital part of the eco-regional network, supporting up to 3 to 4 million staging waterbirds, residents and migrants from all over Europe and western Asia. The hydrological and related ecological conditions in the Inner Delta largely determine the population size of these waterbird species. The major aim of the three-year study was to develop a decision-support system for river management in the Upper Niger, in which ecological and socio-economical impacts and benefits of dams and irrigation systems can be analysed in relation to different water management scenarios. The study involves various components: hydrology, arable farming, livestock, fisheries, ecology and socio-economics. An economic analysis has been conducted to determine the role of dams in the economy of the Inner Niger Delta and the Upper Niger region. By innovatively combining the above information on hydrology, ecology, fisheries, and agriculture, the study shows that building new dams is not an efficient way to increase economic growth and reduce poverty in the region. In fact, such efforts are counter-effective. Instead, development efforts should be aimed at improving the efficiency of the existing infrastructure, as well as of current economic activities in the Inner Niger Delta itself. This approach will also provide greater certainty for the essential eco-regional network functioning of the Inner Delta. © 2006 Taylor & Francis

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

Aspects épidémio-cliniques du paludisme chez les enfants d’âge scolaire au Centre de Référence de la Commune IV du district de Bamako

Nous avons effectué du 2 février 2009 au 1 février 2010 une étude rétrospective sur les aspects épidémiocliniques du paludisme chez les enfants de 5 à 12 ans, au Centre de Santé de Référence de la commune IV du district de Bamako. L’enquête a porté sur 836 sujets dont 302 cas de paludisme diagnostiqué. Les variables cliniques aussi bien que parasitologiques ont été évaluées chez chaque enfant. La goutte épaisse ou le test de diagnostique rapide a été réalisé pour diagnostiquer le paludisme. Nos résultats ont montré que la fièvre intermittente représentait le motif de consultation le plus fréquent, soit 51% des cas. La majorité de nos patients, soit 77,2% ont fait le paludisme simple contre 22,8% de cas de paludisme grave. La goutte épaisse était positive dans 156 cas sur 461 (33,8%) et le test rapide 146 cas de positif sur 375 (38,9%). Le taux de guérison était de 97,7% des cas dont 74,8% (226/302) avec les Combinaisons Thérapeutiques à base d'Artémisinine (CTA). Notre travail a montré que les enfants d’âge scolaire, n’étant pas pris en charge gratuitement par le Programme National de Lutte contre le Paludisme constituent un groupe à risque aussi élevé et méritent une attention particulière tout autant que ceux de moins de cinq ans

Diversity, phenology and distribution of Termitomyces species in Côte d’Ivoire

The mutualistic symbiosis between termites of the Macrotermitinae subfamily (Isoptera: Termitidae) and fungi of the genus Termitomyces (Basidiomycota: Lyophyllaceae) is of great ecological and socio-economic importance. Seasonal fruit bodies of the symbiotic fungi are regularly collected and sold in Côte d’Ivoire. However, there are very few studies on their diversity, phenology, distribution and especially the socio-economic scope of the fruit bodies of these fungi at a national scale. This study aims at (i) assessing the diversity of Termitomyces fruit bodies in Côte d’Ivoire and (ii) mapping their fructification areas through a determination of their spatiotemporal distribution according to a climatic and phytogeographic gradients. Using ethnomycological surveys all over the Ivorian territory, information was collected from rural populations on the fructification of Termitomyces and their socio-economic importance. Based on these surveys, sampling efforts of these fungi were properly structured and oriented. The results revealed a diversity of 16 species of Termitomyces, including 9 species new to Côte d’Ivoire and 2 probably new to science. Five species were found in the forest zone, nine in theGuinean savannah zone and four in the Sudano-Guinean zone. Termitomyces’s fructifications were observed throughout the year, with specific period for each species. All listed species are regularly consumed by populations. However, only Termitomyces letestui (Pat.) R. Heim and Termitomyces schimperi (Pat.) R. Heim are marketed on a relatively large scale

Time Series Analysis of Floods across the Niger River Basin

This study analyses the increasing number of catastrophic floods in the Niger River Basin, focusing on the relation between long term hydro-climatic variability and flood risk over the last 40 to 100 years. Time series for three subregions (Guinean, Sahelian, Benue) show a general consistency between the annual maximum discharge (AMAX) and climatic decadal patterns in West Africa regarding both trends and major changepoints. Variance analysis reveals rather stable AMAX distributions except for the Sahelian region, implying that the changes in flood behavior differ within the basin and affect mostly the dry Sahelian region. The timing of the floods within the year has changed only downstream of the Inner Niger Delta due to retention processes. The results of the hydro-climatic analysis generally correspond to the presented damage statistics on people affected by catastrophic floods. The damage statistics shows positive trends for the entire basin since the beginning in the 1980s, with the most extreme increase in the Middle Niger

Phytogeographical and sociolinguistical patterns of the diversity, distribution, and uses of wild mushrooms in Côte d’Ivoire, West Africa

Abstract Background Many fungal species in tropical Africa are useful, with high added value, and play essential roles in the structure and dynamic of ecosystems. However, the diversity, distribution, and uses by local populations of these non-timber forest products (NTFPs) and their respective habitats are still very poorly understood in sub-Saharan Africa in general and more specifically in Côte d’Ivoire. This study aims at (i) inventorying the wild useful mushrooms of Côte d’Ivoire within its major protected areas and their respective surrounding sociolinguistical groups, according to climatic and phytogeographical gradients, and (ii) recording ethnomycological knowledge and considerations of these local people. Methods Field and ethnomycological surveys were conducted in the main and highest protected areas of Côte d’Ivoire (Comoé, Marahoué, and Taï national parks) and a set of their respective surrounding villages, along climatic and phytogeographical gradients. Standardized methods (permanent plots and opportunistic searches) were used for field surveys. In addition, a total 748 respondents belonging to 13 ethnic groups were interviewed at a rate of 300 interviewees during the preliminary investigations and 448 persons during the proper ethnomycological surveys. Results Sixty-eight useful wild fungal species, belonging to 17 families and 23 genera, were listed and collected. Four categories of usage were reported by the rural people (food, medicinal, belief and recreational), with a dominance of food and medicinal uses. Fifty-six species were reported to be used as food and 16 species as medicinal fungi. These uses varied not only from one sociolinguistical group to another but also from a visited village to another. The high number (41) of the reported useful species was found in the Sudano-Guinean savanna zone while 28 species were collected in the forest zone and 22 species in the forest-savanna mosaic zone. These mushrooms were either saprotrophic or symbiotic (ectomycorrhizal or termitophilic). Auricularia sp3, Psathyrella tuberculata, and Termitomyces spp. were found as the most commonly used mushrooms. Conclusions These national scale field and ethnomycological surveys give one of the more complete but non-exhaustive list of useful mushrooms of Côte d’Ivoire. Mushrooms are relatively well known and used by the Ivorian people within the main phytogeographical zone of the country. These people also have an interest in all the functional groups with an important phytogeographical zone-fungal-specific used species. However, protected areas of the visited zones seem to represent the last sanctuaries of these organisms due to high rate of loss of natural habitats

Les aptitudes agricoles et pastorales des sols dans les pays du CILSS

projet Alerte Précoce et Prévision des Productions Agricoles (AP3A