Publications by authors named "Chaudet H"

Objectives: We aimed to describe coinfections and iterative infections with respiratory viruses diagnosed over a 22-month period in 2021-2022 in public university hospitals of the second largest French city.

Material And Methods: Respiratory virus infections were diagnosed by qPCR with the Fast Track Diagnostics Respiratory Pathogens 21 on nasopharyngeal swabs collected between 01/03/2021-31/10/2022 and sent for routine diagnosis purpose to our clinical microbiology-virology laboratory at public university hospitals of Marseille, Southern France.

Results: Nasopharyngeal swabs from 17,689 patients were tested, of which 8,133 (46 %) were positive for ≥1 respiratory virus and 1,255 (15%) were co-infected with ≥2 viruses including 213 (2.

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Objectives: The SARS-CoV-2 pandemic and large-scale genomic surveillance provided an exceptional opportunity to analyze mutations that appeared over three years in viral genomes. Here we studied mutations and their epidemic consequences for SARS-CoV-2 genomes from our center.

Methods: We analyzed 61,397 SARS-CoV-2 genomes we sequenced from respiratory samples for genomic surveillance.

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Article Synopsis
  • A study found that patients with SARS-CoV-2 infection in the ICU had a higher occurrence of invasive fungal infections, but the effect on airway colonization by fungi wasn't previously evaluated.
  • Researchers analyzed respiratory samples from 2018 to 2022 and conducted a case-control study with 300 patients comparing those with airway colonization to controls.
  • Key factors linked to increased airway colonization included diabetes, mechanical ventilation, hospital stay length, and antibacterial use, while the direct relationship with SARS-CoV-2 was likely influenced by these confounding factors.
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The nature and dynamics of mutations associated with the emergence, spread, and vanishing of SARS-CoV-2 variants causing successive waves are complex. We determined the kinetics of the most common French variant ("Marseille-4") for 10 months since its onset in July 2020. Here, we analyzed and classified into subvariants and lineages 7453 genomes obtained by next-generation sequencing.

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Article Synopsis
  • A COVID-19 outbreak on the French aircraft carrier Charles de Gaulle infected 65% of the crew, with a majority showing specific COVID-19 symptoms, while age and obesity were identified as key risk factors for severe cases.
  • The virus likely entered through multiple sources within France, and physical distancing measures reduced the infection rate significantly.
  • The outbreak went undetected initially due to non-specific symptoms, and the situation improved when enough crew members had been infected, reaching a protective threshold.
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Background: We systematically survey respiratory and gastrointestinal infections of viral origin in samples sent to our university hospital institute in Marseille, southern France. Here, we evaluated whether the measures implemented to fight COVID-19 had an effect on the dynamics of viral respiratory or gastrointestinal infections.

Methods: We analysed PCR performed and positive for the diagnoses of viral respiratory and gastrointestinal infections over five years (January 2017-February 2021).

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Objective: Antibiotic susceptibility testing (AST) is necessary in order to adjust empirical antibiotic treatment, but the interpretation of results requires experience and knowledge. We have developed a machine learning software that is capable of reading AST images without any human intervention and that automatically interprets the AST, based on a database of antibiograms that have been clinically validated with European Committee on Antimicrobial Susceptibility Testing rules.

Methods: We built a database of antibiograms that were labelled by senior microbiologists for three species: Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus.

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After the end of the first epidemic episode of SARS-CoV-2 infections, as cases began to rise again during the summer of 2020, we at IHU Méditerranée Infection in Marseille, France, intensified the genomic surveillance of SARS-CoV-2, and described the first viral variants. In this study, we compared the incidence curves of SARS-CoV-2-associated deaths in different countries and reported the classification of SARS-CoV-2 variants detected in our institute, as well as the kinetics and sources of the infections. We used mortality collected from a COVID-19 data repository for 221 countries.

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From January 18th to August 13th, 2021, 13,804 unvaccinated and 1,156 patients who had received at least one COVID-19 vaccine dose were tested qPCR-positive for SARS-CoV-2 in our center. Among vaccinated patients, 949, 205 and 2 had received a single, two or three vaccine doses, respectively. Most patients (80.

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Background: For the purpose of epidemiological surveillance, the Hospital University Institute Méditerranée infection has implemented since 2013 a system named MIDaS, based on the systematic collection of routine activity materials, including MALDI-TOF spectra, and results. The objective of this paper is to present the pipeline we use for processing MALDI-TOF spectra during epidemiological surveillance in order to disclose proteinic cues that may suggest the existence of epidemic processes in complement of incidence surveillance. It is illustrated by the analysis of an alarm observed for Streptococcus pneumoniae.

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We evaluated the age-specific mortality of unselected adult outpatients infected with SARS-CoV-2 treated early in a dedicated COVID-19 day hospital and we assessed whether the use of hydroxychloroquine (HCQ) + azithromycin (AZ) was associated with improved survival in this cohort. A retrospective monocentric cohort study was conducted in the day hospital of our center from March to December 2020 in adults with PCR-proven infection who were treated as outpatients with a standardized protocol. The primary endpoint was 6-week mortality, and secondary endpoints were transfer to the intensive care unit and hospitalization rate.

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The objective of this paper is to describe the surveillance system MIDaS and to show how this system has been used for evaluating the consequences of the French COVID-19 lockdown on the bacterial mix of AP-HM and the antibiotic resistance. MIDas is a kind of surveillance activity hub, allowing the automatic construction of surveillance control boards. We investigated the diversity and resistance of bacterial agents from respiratory, blood, and urine samples during the lockdown period (from week 12 to 35 of 2020), using the same period of years from 2017 to 2019 as control.

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(1) Background: We collected COVID-19 mortality data and the age distribution of the deceased in France and other European countries, as well as specifically in the cities of Paris and Marseille, and compared them. (2) Methods: Data on mortality related to COVID-19 and the associated age distribution were collected from government institutions in various European countries. In France, data were obtained from INSEE and Santé Publique France.

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In recent years, and more specifically at the beginning of the COVID-19 crisis, wastewater surveillance has been proposed as a tool to monitor the epidemiology of human viral infections. In the present work, from July to December 2020, the number of copies of SARS-CoV-2 RNA in Marseille's wastewater was correlated with the number of new positive cases diagnosed in our Institute of Infectious Disease, which tested about 20% of the city's population. Number of positive cases and number of copies of SARS-CoV-2 RNA in wastewater were significantly correlated ( = 0.

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Objectives: To compare the clinical and epidemiological aspects associated with different predominant lineages circulating in Marseille from March 2020 to January 2021.

Methods: In this single-centre retrospective cohort study, characteristics of patients infected with four different severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants were documented from medical files. The outcome was the occurrence of clinical failure, defined as hospitalization (for outpatients), transfer to the intensive care unit (inpatients) and death (all).

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In late 2019, an epidemic of SARS-CoV-2 broke out in central China. Within a few months, this new virus had spread right across the globe, officially being classified as a pandemic on 11 March 2020. In France, which was also being affected by the virus, the government applied specific epidemiological management strategies and introduced unprecedented public health measures.

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Objectives: The aim was to evaluate the feasibility and diagnostic contribution of protein profiling using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) applied to sputum to diagnose pulmonary tuberculosis.

Methods: Sputum samples collected from patients suspected of having pulmonary tuberculosis were analysed using MALDI-TOF MS. Using the differentially expressed protein peaks, we compared three groups of patients, including those with confirmed pulmonary tuberculosis (PTB), those without tuberculosis but with a lower respiratory tract infection (non-TB LRTI) and those without tuberculosis and without an LRTI (non-TB controls).

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Background: In Marseille, France, the COVID-19 incidence evolved unusually with several successive epidemic phases. The second outbreak started in July, was associated with North Africa, and involved travelers and an outbreak on passenger ships. This suggested the involvement of a new viral variant.

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Respiratory syncytial virus (RSV) is an increasingly recognized cause of acute respiratory infection (ARI) in adults. We compared the crude in-hospital mortality of patients with RSV infection alone with that of patients with RSV-bacterial coinfection. Overall, 12144 hospitalized patients with ARI were screened for RSV detection by polymerase chain reaction between February 2014 and April 2019.

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Objectives: Epidemiological surveillance is one critical approach to estimate and fight the burden of antibiotic resistance (AR). Here we summarise the characteristics of surveillance systems devoted to the surveillance of AR worldwide and published in the literature.

Methods: We performed a systematic review of the literature available on PubMed from January 2007 to July 2019 (12.

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The burden of antibiotic resistance is currently estimated by mathematical modeling, without real count of resistance to key antibiotics. Here we report the real rate of resistance to key antibiotics in bacteria isolated from humans during a 5 years period in a large area in southeast in France. We conducted a retrospective study on antibiotic susceptibility of 539,107 clinical strains isolated from hospital and private laboratories in south of France area from January 2014 to January 2019.

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Objective: To describe the characteristics of COVID-19 patients seen in March-April and June-August 2020 in Marseille, France with the aim to investigate possible changes in the disease between these two time periods.

Methods: Demographics, hospitalization rate, transfer to intensive care unit (ICU), lethality, clinical and biological parameters were investigated.

Results: Compared to those seen in March-April, COVID-19 patients seen in June-August were significantly younger (39.

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Objectives: The SARS-CoV-2 epidemic presents a poorly understood epidemiological cycle. We aimed to compare the age and weekly distributions of the five human coronaviruses, including SARS-CoV-2, that circulated in southeastern France.

Methods: We analyzed all available diagnoses of respiratory viruses, including SARS-CoV-2, performed between 09/2013 and 05/2020 at the University Hospital Institute Méditerranée Infection in Marseille, southeastern France.

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Article Synopsis
  • The study aims to explore how experts make decisions during critical outbreak situations, focusing on both standard and creative strategies when traditional methods fall short.
  • The researchers simulated an outbreak scenario to examine how two experts managed the situation, highlighting the importance of creative problem-solving in epidemiology.
  • The analysis revealed both commonalities and differences in the solutions offered by the experts, which varied based on their level of experience, assessed using Torrance's creativity criteria.
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