Changes in Respiratory Syncytial Virus-Associated Hospitalisations Epidemiology After Nirsevimab Introduction in Lyon, France.

Background: Respiratory Syncytial Virus (RSV) is a major health concern, particularly for infants. In France, Nirsevimab, a long-acting monoclonal antibody to prevent RSV-associated lower respiratory tract infections (LRTI) was available from September 2023. We described RSV-associated LRTI hospitalisations during the 2023-2024 season among infants younger than six months born at the Hospices Civils de Lyon (HCL), and evaluated the effectiveness of Nirsevimab against RSV-LRTI hospitalisation.

Heterogeneity of Clinical Phenotypes in Severe Acute Respiratory Infections due to Respiratory Syncytial Virus: A Need to Look Beyond Hospitalization.

Objective: To use a pre-COVID-19 birth cohort database to describe the clinical heterogeneity of severe acute respiratory infections (SARI) cases of the past seasons as a basis to investigate further distribution of clinical phenotypes in the era of immunization for respiratory syncytial virus (RSV).

Study Design: Infants with RSV-SARI were identified from a 2014 through 2019 birth cohort in a tertiary care center in Lyon, France, and their medical records extensively reviewed. Using the criteria of the World Health Organization severity definitions, we classified SARI as having nutritional (inability to feed), respiratory (SpO<93%), or neurological (failure to respond, apneas) impairments.

Characterizing the interactions between influenza and respiratory syncytial viruses and their implications for epidemic control.

Pathogen-pathogen interactions represent a critical but little-understood feature of infectious disease dynamics. In particular, experimental evidence suggests that influenza virus and respiratory syncytial virus (RSV) compete with each other, such that infection with one confers temporary protection against the other. However, such interactions are challenging to study using common epidemiologic methods.

Intragenomic conflicts with plasmids and chromosomal mobile genetic elements drive the evolution of natural transformation within species.

Natural transformation is the only mechanism of genetic exchange controlled by the recipient bacteria. We quantified its rates in 786 clinical strains of the human pathogens Legionella pneumophila (Lp) and 496 clinical and environmental strains of Acinetobacter baumannii (Ab). The analysis of transformation rates in the light of phylogeny revealed they evolve by a mixture of frequent small changes and a few large quick jumps across 6 orders of magnitude.

Differential impact of COVID-19 non-pharmaceutical interventions on the epidemiological dynamics of respiratory syncytial virus subtypes A and B.

Nonpharmaceutical interventions (NPIs) implemented during the COVID-19 pandemic have disrupted the dynamics of respiratory syncytial virus (RSV) on a global scale; however, the cycling of RSV subtypes in the pre- and post-pandemic period remains poorly understood. Here, we used a two subtype RSV model supplemented with epidemiological data to study the impact of NPIs on the two circulating subtypes, RSV-A and RSV-B. The model is calibrated to historic RSV subtype data from the United Kingdom and Finland and predicts a tendency for RSV-A dominance over RSV-B immediately following the implementation of NPIs.

RSV Severe Infection Risk Stratification in a French 5-Year Birth Cohort Using Machine-learning.

Background: Respiratory syncytial virus (RSV) poses a substantial threat to infants, often leading to challenges in hospital capacity. With recent pharmaceutical developments to be used during the prenatal and perinatal periods aimed at decreasing the RSV burden, there is a pressing need to identify infants at risk of severe disease. We aimed to stratify the risk of developing a clinically severe RSV infection in infants under 1 year of age.

Determining the timing of respiratory syncytial virus (RSV) epidemics: a systematic review, 2016 to 2021; method categorisation and identification of influencing factors.

BackgroundThere is currently no standardised approach to estimate respiratory syncytial virus (RSV) epidemics' timing (or seasonality), a critical information for their effective prevention and control.AimWe aimed to provide an overview of methods to define RSV seasonality and identify factors supporting method choice or interpretation/comparison of seasonal estimates.MethodsWe systematically searched PubMed and Embase (2016-2021) for studies using quantitative approaches to determine the start and end of RSV epidemics.

Biochemical and structural characterization of a class A β-lactamase from Nocardia cyriacigeorgica.

Nocardia are Gram-positive bacteria from the Actinobacteria phylum. Some Nocardia species can infect humans and are usually considered to be opportunist pathogens, as they often infect immunocompromised patients. Although their clinical incidence is low, many Nocardia species are now considered to be emerging pathogens.

The increasing age of respiratory syncytial virus-related hospitalisation during COVID-19 pandemic in Lyon was associated with reduced hospitalisation costs.

Background: Preventive measures applied during the COVID-19 pandemic have modified the age distribution, the clinical severity and the incidence of Respiratory Syncytial Virus (RSV) hospitalisations during the 2020/21 RSV season. The aim of the present study was to estimate the impact of these aspects on RSV-associated hospitalisations (RSVH) costs stratified by age group between pre-COVID-19 seasons and 2020/21 RSV season.

Methods: We compared the incidence, the median costs, and total RSVH costs from the national health insurance perspective in children < 24 months of age during the COVID-19 period (2020/21 RSV season) with a pre-COVID-19 period (2014/17 RSV seasons).

The impact of the SARS-CoV-2 pandemic on global influenza surveillance: Insights from 18 National Influenza Centers based on a survey conducted between November 2021 and March 2022.

Background: National Influenza Centers (NICs) have played a crucial role in the surveillance of SARS-CoV-2. The FluCov project, covering 22 countries, was initiated to monitor the impact of the SARS-CoV-2 pandemic on influenza activity.

Methods: This project consisted of an epidemiological bulletin and NIC survey.

Importance of the 2,6-Difluorobenzamide Motif for FtsZ Allosteric Inhibition: Insights from Conformational Analysis, Molecular Docking and Structural Modifications.

A conformational analysis and molecular docking study comparing 2,6-difluoro-3-methoxybenzamide (DFMBA) with 3-methoxybenzamide (3-MBA) has been undertaken for investigating the known increase of FtsZ inhibition related anti activity due to fluorination. For the isolated molecules, the calculations reveal that the presence of the fluorine atoms in DFMBA is responsible for its non-planarity, with a dihedral angle of -27° between the carboxamide and the aromatic ring. When interacting with the protein, the fluorinated ligand can thus more easily adopt the non-planar conformation found in reported co-crystallized complexes with FtsZ, than the non-fluorinated one.

The role of skin dysbiosis in atopic dermatitis.

The cutaneous microbiota contributes to skin barrier function, ensuring effective protection against pathogens and contributing to the maintenance of epidermal integrity. Dysbiosis is frequently present in atopic dermatitis (AD), a chronic inflammatory disease associated with skin barrier defects. Dysbiosis is associated with reduced bacterial diversity and marked Staphylococcus aureus colonization, which is favoured in the case of certain local AD-specific properties such as reduced skin acidity, eased bacterial adhesion and decreased antimicrobial peptide production.

Structural Variations in the Central Heterocyclic Scaffold of Tripartite 2,6-Difluorobenzamides: Influence on Their Antibacterial Activity against MDR .

Five series of heterocyclic tripartite 2,6-difluorobenzamides, namely 1,2,3-triazoles, 1,2,4- and 1,3,4-oxadiazoles, analogs of reported model anti-staphylococcal compounds, were prepared. The purpose was to investigate the influence of the nature of the heterocyclic central scaffold on the biological activity against three strains of including two drug-resistant ones. Among the 15 compounds of the new collection, a 3-(4--butylphenyl)-1,2,4-oxadiazole linked via a methylene group with a 2,6-difluorobenzamide moiety () exhibited a minimal inhibitory concentration between 0.

Global, regional, and national disease burden estimates of acute lower respiratory infections due to respiratory syncytial virus in children younger than 5 years in 2019: a systematic analysis.

Background: Respiratory syncytial virus (RSV) is the most common cause of acute lower respiratory infection in young children. We previously estimated that in 2015, 33·1 million episodes of RSV-associated acute lower respiratory infection occurred in children aged 0-60 months, resulting in a total of 118 200 deaths worldwide. Since then, several community surveillance studies have been done to obtain a more precise estimation of RSV associated community deaths.

IgA Serological Response for the Diagnosis of Mycobacterium abscessus Infections in Patients with Cystic Fibrosis.

The immunoglobulin A (IgA) status of cystic fibrosis (CF) patients, presenting with or without a non-tuberculous mycobacterial (NTM) infection, has to date not been fully elucidated toward two antigenic preparations previously described. We have chosen to determine the clinical values of an IgA ELISA for the diagnosis of NTM and/or Mycobacterium abscessus infections in CF patients. One hundred and 73 sera from CF patients, comprising 33 patients with M.

Evaluation of commercial Anti-SARS-CoV-2 neutralizing antibody assays in seropositive subjects.

The virus neutralization test (VNT) is the reference for the assessment of the functional ability of neutralizing antibodies (NAb) to block SARS-CoV-2 entry into cells. New competitive immunoassays measuring antibodies preventing interaction between the spike protein and its cellular receptor are proposed as surrogate VNT (sVNT). We tested three commercial sVNT (a qualitative immunochromatographic test and two quantitative immunoassays named YHLO and TECO) together with a conventional anti-spike IgG assay (bioMérieux) in comparison with an in-house plaque reduction neutralization test (PRNT) using the original 19A strain and different variants of concern (VOC), on a panel of 306 sera from naturally-infected or vaccinated patients.

Synthesis and Biological Evaluation of Benzo[]thiophene Acylhydrazones as Antimicrobial Agents against Multidrug-Resistant .

The benzo[]thiophene nucleus and the acylhydrazone functional group were combined to prepare three new series of compounds for screening against . The reaction of substituted benzo[]thiophene-2-carboxylic hydrazide and various aromatic or heteroaromatic aldehydes led to a collection of 26 final products with extensive structural diversification on the aromatic ring and on position 6 of the benzo[]thiophene nucleus. The screening lead to the identification of eight hits, including ()-6-chloro-'-(pyridin-2-ylmethylene)benzo[]thiophene-2-carbohydrazide (), a non-cytotoxic derivative showing a minimal inhibitory concentration of 4 µg/mL on three strains, among which were a reference classical strain and two clinically isolated strains resistant to methicillin and daptomycin, respectively.

Sub-Inhibitory Concentrations of Oxacillin, but Not Clindamycin, Linezolid, or Tigecycline, Decrease Staphylococcal Phenol-Soluble Modulin Expression in Community-Acquired Methicillin-Resistant Staphylococcus aureus.

Staphylococcus aureus (SA) is a major human pathogen producing virulence factors, such as Panton-Valentine-leucocidin (PVL), alpha-hemolysin (Hla), and phenol-soluble-modulins alpha (PSMα), including delta-hemolysin (Hld). Unlike oxacillin, clindamycin and linezolid subinhibitory concentrations (sub-MIC) display an anti-toxin effect on PVL and Hla expression. Few studies have investigated PSMα and Hld expression modulation by antibiotics.

Evaluation of Commercial Anti-SARS-CoV-2 Antibody Assays and Comparison of Standardized Titers in Vaccinated Health Care Workers.

With the availability of vaccines, commercial assays detecting anti-severe acute respiratory syndrome coronavirus-2 antibodies (Ab) evolved toward quantitative assays directed to the spike glycoprotein or its receptor binding domain (RBD). The main objective of the present study was to compare the Ab titers obtained with quantitative commercial binding Ab assays, after one dose (convalescent individuals) or two doses (naive individuals) of vaccine, in health care workers (HCW). Antibody titers were measured in 255 sera (from 150 HCW) with five quantitative immunoassays (Abbott RBD IgG II quant, bioMérieux RBD IgG, DiaSorin Trimeric spike IgG, Siemens Healthineers RBD IgG, Wantai RBD IgG).

Serological biomarkers for the diagnosis of Mycobacterium abscessus infections in cystic fibrosis patients.

Background: Culture conditions sometimes make it difficult to detect non-tuberculous mycobacteria (NTM), particularly Mycobacterium abscessus, an emerging cystic fibrosis (CF) pathogen. The diagnosis of NTM positive cases not detected by classical culture methods might benefit from the development of a serological assay.

Methods: As part of a diagnostic accuracy study, a total of 173 sera CF-patients, including 33 patients with M.

Characteristics of the delayed respiratory syncytial virus epidemic, 2020/2021, Rhône Loire, France.

The Rhône-Loire metropolitan areas' 2020/21 respiratory syncytial virus (RSV) epidemic was delayed following the implementation of non-pharmaceutical interventions (NPI), compared with previous seasons. Very severe lower respiratory tract infection incidence among infants ≤ 3 months decreased twofold, the proportion of cases among children aged > 3 months to 5 years increased, and cases among adults > 65 years were markedly reduced. NPI appeared to reduce the RSV burden among at-risk groups, and should be promoted to minimise impact of future RSV outbreaks.

The MTB/MDR ELITe MGB Kit: Performance Assessment for Pulmonary, Extra-Pulmonary, and Resistant Tuberculosis Diagnosis, and Integration in the Laboratory Workflow of a French Center.

A rapid and reliable diagnostic for tuberculosis, including the detection of both rifampicin (RIF) and isoniazid (INH) resistance, is essential for appropriate patient care. Nucleic acid amplification tests are a fast alternative to methods based on complex (MTB) cultures. Thus, the performance of the MDR/MTB ELITe MGB Kit on the ELITe InGenius platform was retrospectively evaluated for MTB detection on pulmonary and extra-pulmonary samples and for RIF/INH resistance detection on MTB strains.

Staphylococcal Panton-Valentine Leucocidin and Gamma Haemolysin Target and Lyse Mature Bone Marrow Leucocytes.

is a major human pathogen, inducing several infections ranging from the benign to the life-threatening, such as necrotising pneumonia. is capable of producing a great variety of virulence factors, such as bicomponent pore-forming leucocidin, which take part in the physiopathology of staphylococcal infection. In necrotising pneumonia, Panton-Valentine leucocidin (PVL) induces not only lung injury and necrosis, but also leukopenia, regarded as a major factor of a poor prognosis.

[Spider bite or infection caused by Panton Valentine leucocidin-producing Staphylococcusaureus?].

Introduction: Spiders, especially those of the genus Loxoceles such as L. rufescens, endemic in Mediterranean regions, are frequently reported as causes of venom poisoning in humans in the south of France. The most common signs consist of cutaneous necrosis presenting initially as inflammatory cellulitis and progressing towards the emergence of a necrotic centre.