Influence des facteurs telluriques abiotiques et de la plante hôte sur l'infection des nématodes phytoparasites du genre Meloidogyne par l'actinomycète parasitoïde Pasteuria penetrans

Une prospection nématologique a été réalisée dans 4 grandes régions maraîchères du Sénégal (Cap Vert, Pays Sereer, Niayes et Fleuve Sénégal). #Pasteuria penetrans, actinomycète parasitoïde des nématodes du genre #Meloidogyne, a été rencontré dans toutes les zones prospectées à une fréquence moyenne de 30% des échantillons, mais il est très peu abondant (8% des juvéniles de #Meloidogyne$ parasités en moyenne). Sa distribution est liée à la texture et à la structure des sols. Les sols sableux sont plus propices que les sols argileux à l'adhésion des spores de l'actinomycète sur les juvéniles du nématode mais, dans les sols sableux, la présence d'argile faciliterait la conservation des spores dans le sol. La plante hôte du nématode joue aussi un rôle sur le développement du parasitoïde soit en améliorant les conditions environnementales de l'adhésion par l'intermédiaire des exsudats racinaires, soit en facilitant sa multiplication dans la cavité générale du nématode infestant. (Résumé d'auteur

EPIdemiology of Surgery-Associated Acute Kidney Injury (EPIS-AKI) : Study protocol for a multicentre, observational trial

More than 300 million surgical procedures are performed each year. Acute kidney injury (AKI) is a common complication after major surgery and is associated with adverse short-term and long-term outcomes. However, there is a large variation in the incidence of reported AKI rates. The establishment of an accurate epidemiology of surgery-associated AKI is important for healthcare policy, quality initiatives, clinical trials, as well as for improving guidelines. The objective of the Epidemiology of Surgery-associated Acute Kidney Injury (EPIS-AKI) trial is to prospectively evaluate the epidemiology of AKI after major surgery using the latest Kidney Disease: Improving Global Outcomes (KDIGO) consensus definition of AKI. EPIS-AKI is an international prospective, observational, multicentre cohort study including 10 000 patients undergoing major surgery who are subsequently admitted to the ICU or a similar high dependency unit. The primary endpoint is the incidence of AKI within 72 hours after surgery according to the KDIGO criteria. Secondary endpoints include use of renal replacement therapy (RRT), mortality during ICU and hospital stay, length of ICU and hospital stay and major adverse kidney events (combined endpoint consisting of persistent renal dysfunction, RRT and mortality) at day 90. Further, we will evaluate preoperative and intraoperative risk factors affecting the incidence of postoperative AKI. In an add-on analysis, we will assess urinary biomarkers for early detection of AKI. EPIS-AKI has been approved by the leading Ethics Committee of the Medical Council North Rhine-Westphalia, of the Westphalian Wilhelms-University Münster and the corresponding Ethics Committee at each participating site. Results will be disseminated widely and published in peer-reviewed journals, presented at conferences and used to design further AKI-related trials. Trial registration number NCT04165369

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

Influence des facteurs telluriques abiotiques et de la plante hôte sur l'infection des nématodes phytoparasites du genre Meloidogyne par l'actinomycète parasitoïde Pasteuria penetrans

Une prospection nématologique a été réalisée dans 4 grandes régions maraîchères du Sénégal (Cap Vert, Pays Sereer, Niayes et Fleuve Sénégal). #Pasteuria penetrans, actinomycète parasitoïde des nématodes du genre #Meloidogyne, a été rencontré dans toutes les zones prospectées à une fréquence moyenne de 30% des échantillons, mais il est très peu abondant (8% des juvéniles de #Meloidogyne$ parasités en moyenne). Sa distribution est liée à la texture et à la structure des sols. Les sols sableux sont plus propices que les sols argileux à l'adhésion des spores de l'actinomycète sur les juvéniles du nématode mais, dans les sols sableux, la présence d'argile faciliterait la conservation des spores dans le sol. La plante hôte du nématode joue aussi un rôle sur le développement du parasitoïde soit en améliorant les conditions environnementales de l'adhésion par l'intermédiaire des exsudats racinaires, soit en facilitant sa multiplication dans la cavité générale du nématode infestant. (Résumé d'auteur