8 research outputs found

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

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    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

    La réception de Brecht en Afrique chez Wolé Soyinka, Alioum Fantouré et Ngugi wa Thiong'o

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    La réception de Brecht chez Wolé Soyinka, Alioum Fantouré et Ngugi wa Thiong'o montre une certaine liberté que les auteurs africains s'octroient avec le texte de Brecht et qui nous fait réfléchir sur le rapport parfois ambivalent entre le regard que le "je" de ces auteurs porte sur "l'autre" qui est ici Brecht et ce que Brecht est en réalité. Dans le cas spécifique de Soyinka, de Fantouré et, dans une moindre mesure, de Ngugi, cette lecture devient une sorte de relecture de "l'autre" Brecht qui se voit ainsi "domestiqué" au point de devenir désormais, thématiquement et stylistiquement, un élément local dans leur complexe littéraire. Alors que Soyinka réactualise la tradition yoruba avec Brecht en toile de fond, faisant ressortir les éléments dramatiques qui interviennent dans les deux traditions africaine et européeenne, mais avec des fonctions poétiques différentes, Fantouré montre une réception ponctuelle et limitée à la reprise du cercueil de zinc dans Le Cercle des Tropiques, séparant toutefois le politique de l'idéologique. Seul Ngugi, de tendance marxiste, donne à la réception de Brecht, des contours plus affirmés avec un recours marqué au dramaturge allemand.STRASBOURG-B.N.U.S. (674821001) / SudocSudocFranceF

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

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    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

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

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    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

    Soil fungal communities of ectomycorrhizal dominated woodlands across West Africa

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    Forests and woodlands in the West African Guineo-Sudanian transition zone contain many tree species that form symbiotic interactions with ectomycorrhizal (ECM) fungi. These fungi facilitate plant growth by increasing nutrient and water uptake and include many fruiting body-forming fungi, including some edible mushrooms. Despite their importance for ecosystem functioning and anthropogenic use, diversity and distribution of ECM fungi is severely under-documented in West Africa. We conducted a broad regional sampling across five West African countries using soil eDNA to characterize the ECM as well as the total soil fungal community in gallery forests and savanna woodlands dominated by ECM host tree species. We subsequently sequenced the entire ITS region and much of the LSU region to infer a phylogeny for all detected soil fungal species. Utilizing a long read sequencing approach allows for higher taxonomic resolution by using the full ITS region, while the highly conserved LSU gene allows for a more accurate higher-level assignment of species hypotheses, including species without ITS-based taxonomy assignments. We detect no overall difference in species richness between gallery forests and woodlands. However, additional gallery forest plots and more samples per plot would have been needed to firmly conclude this pattern. Based on both abundance and richness, species from the families Russulaceae and Inocybaceae dominate the ECM fungal soil communities across both vegetation types. The community structure of both total soil fungi and ECM fungi was significantly influenced by vegetation types and showed strong correlation within plots. However, we found no significant difference in fungal community structure between samples collected adjacent to different host tree species within each plot. We conclude that within plots, the fungal community is structured more by the overall ECM host plant community than by the species of the individual host tree that each sample was collected from.Peter Meidl and Brendan Furneaux contributed equally as first authors. Kassim Tchan and Kerri Klut-ing contributed equally as second authors.</p

    Clinical Outcomes during Treatment Interruptions in Human Immunodeficiency Virus-Hepatitis B Virus Co-infected Patients from Sub-Saharan Africa

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    Antiretroviral treatment (ART) interruptions increase the risk of severe morbidity/mortality in human immunodeficiency virus (HIV)-infected individuals from subSaharan Africa. We aimed to determine whether the risk is further increased among HIV-hepatitis B virus (HBV) co-infected patients in this setting. In this sub-analysis of a randomized-control trial, 632 participants from CĂ´te d'Ivoire randomized to receive continuous-ART (C-ART), structured ART interruptions of 2-months off, 4-months on (2/4-ART), and CD4-guided ART interruptions (CD4GT, interruption at 350/mm3 and reintroduction at 250/mm3) were analyzed. Incidence rates (IR) of serious HIV- and non-HIV-related morbidity were compared between patients stratified on hepatitis B surface antigen (HBsAg) status. Overall, 65 (10.3%) were HBsAg-positive, 29 (44.6%) of whom had HBV-DNA levels > 10,000 copies/mL. After a median 2.0 year (range = 0.2-3.1) followup, 3 1 serious HIV-related events occurred in 101 HIV mono-infected and 15 HIV-HBV co-infected patients (IR = 10.0 versus 13.2/100 person/years, respectively, P = 0.3), whereas the highest incidence was observed in co-infected patients with baseline HBV-replication > 10,000 copies/mL (IR = 24.0/100 person/years, P versus HIV mono-infected = 0.002). Incidence of bacterial infections was also highest in the co-infected group with HBV-replication > 10,000 copies/mL (IR = 12.9 versus 3.3/100 person/years in HIV mono-infected patients, P = 0.001). The relative effect of CD4GT or 2/4-ART versus C-ART was not different between infection groups (P for interaction = 0.4). No increase in the incidence of non-HIV-related morbidity was observed for co-infected patients (P = 0.5), even at HBV-replication levels > 10,000 copies/mL (P = 0.7). In conclusion, co-infected patients with elevated HBV-replication at ART-initiation are more susceptible to HIV-related morbidity, especially invasive bacterial diseases, during treatment interruption
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