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

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Microbial culturomics to isolate halophilic bacteria from table salt: genome sequence and description of the moderately halophilic bacterium Bacillus salis sp. nov.

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500m gridded surfaces for changes in climate suitability for coffee production in Risaralda, Colombia

We used 500m gridded historical and future climate surfaces for Risaralda, Colombia and coffee presences and absences to train species distribution models (suitability). Five methods were used: Generalized Boosting Model (GBM) (Friedman, 2001), Random Forest (RF) (Breiman, 2001), Maxent (Phillips et al., 2006), Generalized Linear Model (GLM) and Generalized Additive Model (GAM) (Guisan et al., 2002)

Massilimicrobiota timonensis gen. nov., sp. nov., a new bacterium isolated from the human gut microbiota

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Olsenella timonensis sp. nov., a new bacteria species isolated from the human gut microbiota

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Massilistercora timonensis gen. nov., sp. nov., a new bacterium isolated from the human microbiota

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Genome sequence and description of Urinicoccus timonensis gen. nov., sp. nov., a new bacterium isolated from a human stool sample

International audienceUrinicoccus timonensis gen. nov., sp. nov. strain Marseille-P3926(T) is a new species from the phylum Firmicutes and the family Peptoniphilaceae that was isolated from a human faeces sample. Genome was 1 978 908 bp long with a 41.1 G + C content. The closest species based on 16S ribosomal RNA was Peptoniphilus ivorii DSM 10022 with 90.8% sequence similarity. Considering phenotypic features, 16S rRNA sequence and comparative genome studies, we proposed Marseille-P3926(T) as the strain type of Urinicoccus timonensis gen. nov., sp. nov. (C) 2020 The Authors. Published by Elsevier Ltd

Anaerococcus marasmi sp. nov., a new bacterium isolated from human gut microbiota

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Lactimicrobium massiliense gen. nov., sp. nov.; Anaerolactibacter massiliensis gen. nov., sp. nov.; Galactobacillus timonensis gen. nov., sp. nov. and Acidipropionibacterium timonense sp. nov. isolated from breast milk from healthy breastfeeding African women

Four strains isolated by microbial culturomics from breast milk of healthy mothers from Mali were not identified and characterized by taxono-genomics. This led us to propose the new genera and species Lactimicrobium massiliense, Anaerolactibacter massiliensis and Galactobacillus timonensis containing type strain Marseille-P4301T (CSUR P4301T), Marseille-P4302T (CSUR P4302T) and Marseille-P4641T (CSUR P4641T), respectively. The strain Marseille-P4482 represents a novel species, Acidipropionibacterium timonense, in a previously known genus with type strain being Marseille-P4482T (CSUR P4482T). Keywords: Culturomics, human breast milk, microbiome, microbiota, taxono-genomic