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International audience; Corona-Virus Disease (COVID-19), caused by the novel Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2) has been spreading rapidly worldwide causing the world to face a global health crisis. Countries are experiencing a new wave of contamination and are witnessing spikes in the disease without being able to control its spread again. This paper aims to analyze the mortality rate related to the COVID-19 pandemic infection in Tunisia and to assess the effectiveness of health control policies. Data collection for this document was stopped on October, 31 st , 2020.

Abstract Background The Marburg virus (MARV) has a negative-sense single-stranded RNA genome, belongs to the family Filoviridae, and is responsible for several outbreaks of highly fatal hemorrhagic fever. Codon usage patterns of viruses reflect a series of evolutionary changes that enable viruses to shape their survival rates and fitness toward the external environment and, most importantly, their hosts. To understand the evolution of MARV at the codon level, we report a comprehensive analysis of synonymous codon usage patterns in MARV genomes. Multiple codon analysis approaches and statistical methods were performed to determine overall codon usage patterns, biases in codon usage, and influence of various factors, including mutation pressure, natural selection, and its two hosts, Homo sapiens and Rousettus aegyptiacus. Results Nucleotide composition and relative synonymous codon usage (RSCU) analysis revealed that MARV shows mutation bias and prefers U- and A-ended codons to code amino acids. Effective number of codons analysis indicated that overall codon usage among MARV genomes is slightly biased. The Parity Rule 2 plot analysis showed that GC and AU nucleotides were not used proportionally which accounts for the presence of natural selection. Codon usage patterns of MARV were also found to be influenced by its hosts. This indicates that MARV have evolved codon usage patterns that are specific to both of its hosts. Moreover, selection pressure from R. aegyptiacus on the MARV RSCU patterns was found to be dominant compared with that from H. sapiens. Overall, mutation pressure was found to be the most important and dominant force that shapes codon usage patterns in MARV. Conclusions To our knowledge, this is the first detailed codon usage analysis of MARV and extends our understanding of the mechanisms that contribute to codon usage and evolution of MARV.

A large proportion of SARS-CoV-2 infected individuals remains asymptomatic. Little is known about the extent and quality of their antiviral humoral response. Here, we analyze antibody functions in 52 asymptomatic infected individuals, 119 mild and 21 hospitalized COVID-19 patients. We measured anti-Spike IgG, IgA and IgM levels with the S-Flow assay and map IgG-targeted epitopes by Luminex. We also evaluated neutralization, complement deposition and Antibody-Dependent Cellular Cytotoxicity (ADCC) using replication-competent SARS-CoV-2 or reporter cell systems. We show that COVID-19 sera mediate complement deposition and kill infected cells by ADCC. Sera from asymptomatic individuals neutralize the virus, activate ADCC and trigger complement deposition. Antibody levels and functions are lower in asymptomatic individuals than in symptomatic cases. Antibody functions are correlated, regardless of disease severity. Longitudinal samplings show that antibody functions follow similar kinetics of induction and contraction. Overall, asymptomatic SARS-CoV-2 infection elicits polyfunctional antibodies neutralizing the virus and targeting infected cells. Dufloo et al. show that SARS-CoV-2 infection elicits antibodies that neutralize the virus, activate the complement system and kill infected cells by ADCC. These polyfunctional antibodies are slightly more abundant in symptomatic COVID-19 patients than in asymptomatic individuals and correlate with disease severity. Graphical Abstract

International audience; Bronchopulmonary infections are a major trigger of cardiac decompensation and are frequently associated with hospitalizations in patients with heart failure (HF). Adverse cardiac effects associated with respiratory infections, more specifically Streptococcus pneumoniae and influenza infections, are the consequence of inflammatory processes and thrombotic events. For both influenza and pneumococcal vaccinations, large multicenter randomized clinical trials are needed to evaluate their efficacy in preventing cardiovascular events, especially in HF patients. No study to date has evaluated the protective effect of the COVID-19 vaccine in patients with HF. Different guidelines recommend annual influenza vaccination for patients with established cardiovascular disease and also recommend pneumococcal vaccination in patients with HF. The Heart Failure group of the French Society of Cardiology recently strongly recommended vaccination against COVID-19 in HF patients. Nevertheless, the implementation of vaccination recommendations against respiratory infections in HF patients remains suboptimal. This suggests that a national health policy is needed to improve vaccination coverage, involving not only the general practitioner, but also other health providers, such as cardiologists, nurses, and pharmacists. This review first summarizes the pathophysiology of the interrelationships between inflammation, infection, and HF. Then, we describe the current clinical knowledge concerning the protective effect of vaccines against respiratory diseases (influenza, pneumococcal infection, and COVID-19) in patients with HF and finally we propose how vaccination coverage could be improved in these patients.

International audience; We introduce Seshat, a new, simple and open-source software to efficiently manage annotations of speech corpora. The Seshat software allows users to easily customise and manage annotations of large audio corpora while ensuring compliance with the formatting and naming conventions of the annotated output files. In addition, it includes procedures for checking the content of annotations following specific rules that can be implemented in personalised parsers. Finally, we propose a double-annotation mode, for which Seshat computes automatically an associated inter-annotator agreement with the γ measure taking into account the categorisation and segmentation discrepancies.; Nous introduisons Seshat, un nouveau logiciel libre permettant d'efficacement gérer l'annotation de corpora de parole. Le logiciel Seshat permet aux utilisateurs de facilement spécifier et gérer l'annotation de corpora d'audio conséquents, tout en s'assurant que les fichiers des annotations respectent des conventions de formattage et de nommage prédéfinies. En outre, des procédures de vérification du contenu des annotations sont livrées dans Seshat, avec la possibilité d'inclure des parsers externes. Finalement, nous proposons un mode dit de "double annotation", dans lequel Seshat calcule automatiquement une mesure de la concordance inter-annotateur avec la mesure γ, qui prend en compte les différences de catégorisation et de segmentation.

International audience; A 6-y-old neutered male ferret (Mustela putorius furo) was presented because of a 1-mo history of progressive weight loss, chronic cough, and hair loss. On clinical examination, the animal was coughing, slightly depressed, moderately hypothermic, and had bilateral epiphora. Thoracic radiography was suggestive of severe multinodular interstitial pneumonia. Abdominal ultrasound examination revealed hepatosplenomegaly and mesenteric and pancreaticoduodenal lymphadenopathy. Fine-needle aspiration of the pancreaticoduodenal lymph node, followed by routine Romanowsky and Ziehl-Neelsen stains, revealed numerous macrophages containing myriad acid-fast bacilli, leading to identification of mycobacteriosis. Autopsy and histologic examination confirmed the presence of disseminated, poorly defined, acid-fast, bacilli-rich granulomas in the pancreaticoduodenal and mesenteric lymph nodes, intestines, and lungs. Destaining of May-Grunwald/Giemsa-stained slides with alcohol, and then restaining with Ziehl-Neelsen, revealed acid-fast rods and avoided repeat tissue sampling without affecting the Ziehl-Neelsen stain quality and cytologic features. Tissue samples were submitted for a PCR assay targeting the heat shock protein gene (hsp65) and revealed 100% homology with Mycobacterium genavense. We emphasize the use of special stains and PCR for identification of this potential zoonotic agent.

The capacity of the surface glycoproteins of enveloped viruses to mediate virus/cell binding and membrane fusion requires a proper thiol/disulfide balance. Chemical manipulation of their redox state using reducing agents or free sulfhydryl reagents affects virus/cell interaction. Conversely, natural thiol/disulfide rearrangements often occur during the cell interaction to trigger fusogenicity, hence the virus entry. We examined the relationship between the redox state of the 20 cysteine residues of the SARS-CoV (severe acute respiratory syndrome coronavirus) Spike glycoprotein S1 subdomain and its functional properties. Mature S1 exhibited approximately 4 unpaired cysteines, and chemically reduced S1 displaying up to approximately 6 additional unpaired cysteines still bound ACE2 and enabled fusion. In addition, virus/cell membrane fusion occurred in the presence of sulfhydryl-blocking reagents and oxidoreductase inhibitors. Thus, in contrast to various viruses including HIV (human immunodeficiency virus) examined in parallel, the functions of the SARS-CoV Spike glycoprotein exhibit a significant and surprising independence of redox state, which may contribute to the wide host range of the virus. These data suggest clues for molecularly engineering vaccine immunogens.

International audience; On March 11, 2020, the World Health Organization declared the coronavirus disease 2019 (COVID-19) outbreak as a pandemic, with over 720,000 cases reported in more than 203 countries as of 31 March. The response strategy included early diagnosis, patient isolation, symptomatic monitoring of contacts as well as suspected and confirmed cases, and public health quarantine. In this context, telemedicine, particularly video consultations, has been promoted and scaled up to reduce the risk of transmission, especially in the United Kingdom and the United States of America. Based on a literature review, the first conceptual framework for telemedicine implementation during outbreaks was published in 2015. An updated framework for telemedicine in the COVID-19 pandemic has been defined. This framework could be applied at a large scale to improve the national public health response. Most countries, however, lack a regulatory framework to authorize, integrate, and reimburse telemedicine services, including in emergency and outbreak situations. In this context, Italy does not include telemedicine in the essential levels of care granted to all citizens within the National Health Service, while France authorized, reimbursed, and actively promoted the use of telemedicine. Several challenges remain for the global use and integration of telemedicine into the public health response to COVID-19 and future outbreaks. All stakeholders are encouraged to address the challenges and collaborate to promote the safe and evidence-based use of telemedicine during the current pandemic and future outbreaks. For countries without integrated telemedicine in their national health care system, the COVID-19 pandemic is a call to adopt the necessary regulatory frameworks for supporting wide adoption of telemedicine.

International audience; Background and objectives Dialysis patients have a high mortality risk after coronavirus disease 2019 (COVID-19) and an altered immunologic response to vaccines, but vaccine clinical effectiveness remains unknown in this population. Design, setting, participants, & measurements Using Bayesian multivariable spatiotemporal models, we estimated the association between vaccine exposure and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) severe infections (with hospital admission) in dialysis patients from simultaneous incidence in the general population. For dialysis patients, cases were reported within the French end-stage kidney disease REIN registry from March 11, 2020, to April 29, 2021, and vaccine exposure (first dose) was reported in weekly national surveys since January 2021. Cases in the general population were obtained from the national exhaustive inpatient surveillance system (SI-VIC database), and vaccination coverage (first dose) was obtained from the national surveillance system (VAC-SI database). Results During the first wave, incidence in dialysis patients was approximately proportional to the general population. However, we showed a lower relative incidence for dialysis patients during the second wave (compared with that observed in nondialysis patients), suggesting an effect of prevention measures. Moreover, from the beginning of the vaccination rollout, incidence in dialysis patients was lower compared with predictions based on the first and second waves. Adding vaccination coverages in dialysis and nondialysis patients as predictors allowed the reported cases to be fit correctly (3685 predicted cases, 95% confidence interval, 3552 to 3816, versus 3620 reported). Incidence rate ratios were 0.37 (95% confidence interval, 0.18 to 0.71) for vaccine exposure in dialysis patients and 0.50 (95% confidence interval, 0.40 to 0.61) per 10% higher in vaccination coverage in the same-age general population, meaning that vaccine exposure in dialysis patients and the general population was independently associated with lower hospitalization rate of dialysis patients. Conclusions Our findings suggest that vaccination may yield a protective effect against severe forms of COVID-19 in dialysis patients, despite altered immunologic vaccine responses.

Recent studies based on observations have shown the impact of lockdown measures taken in various European countries to contain the Covid-19 pandemic on air quality. However, these studies are often limited to compare situations without and with lockdown measures, which correspond to different time periods and then under different meteorological conditions. We propose a modelling study with the WRF-CHIMERE modelling suite for March 2020, an approach allowing to compare atmospheric composition with and without lockdown measures without the biases of meteorological conditions. This study shows that the lockdown effect on atmospheric composition, in particular through massive traffic reductions, has been important for several short-lived atmospheric trace species, with a large reduction in NO2 concentrations, a lower reduction in Particulate Matter (PM) concentrations and a mitigated effect on ozone concentrations due to non-linear chemical effects. Highlights • Air pollution modelling • COVID19 epidemy • Regional modelling • Anthropogenic emissions scenario • Impact of emissions reduction Graphical abstract Unlabelled Image