Explore the vast range of titles available.

To identify factors associated with vaginal colonization and persistence by group B Streptococcus (GBS) and by the hypervirulent neonatal CC-17 clone in late pregnancy and after delivery, a multicentre prospective observational cohort with 3-month follow-up was established in two university hospitals, Paris area, France. Pregnant women were recruited when antenatal screening for GBS vaginal colonization at 34–38 weeks of gestational age was positive. Vaginal samples were analysed by conventional culture methods at antenatal screening, delivery, and 21 and 60 days following delivery. Identification of the hypervirulent neonatal GBS CC-17 was performed. Colonization was defined as persistent when all vaginal samples were positive for GBS. A total of 754 women were included. GBS vaginal colonization was persistent in 63% of the cases (95% CI 59%–67%). Persistent colonization was more likely in women born in Sub-Saharan Africa compared with women born in France (OR = 1.88, 95% CI 1.05–3.52), and GBS CC-17 was overrepresented in women born in Sub-Saharan Africa (OR = 2.09, 95% CI 1.20–3.57). Women born in Sub-Saharan Africa are at higher risk for GBS vaginal persistence than women born in France. This observation correlates with an increased prevalence of the hypervirulent GBS CC-17 in the former group, which likely reflect variations linked to ethnicity and vaginal community-state types and might account for the increased susceptibility of black neonates to GBS infections.

Purpose To characterize Escherichia coli ventilator-associated pneumonia (VAP) in intensive care unit (ICU) patients by determining antibioresistance and genotypic characteristics of E. coli isolates responsible for VAP or lung colonization, by comparing them with their oropharyngeal and rectal counterparts and by assessing representative isolates’ virulence in a pneumonia mouse model. Methods Patients under mechanical ventilation for more than 72 h were screened for simultaneous presence of E. coli in rectal, oropharyngeal, and respiratory samples (colonization or VAP). If present, E. coli isolates were characterized by antimicrobial susceptibility, phylogenetic grouping, and virulence factor (VF) gene content determination. BALB/c mice were challenged intranasally with 3.6 × 10 8 colony-forming units (CFU) of patients’ E. coli isolates. Results Multisite E. coli colonization was observed in 19 % of patients (25 patients, 12 with E. coli VAP). One hundred fifteen distinct E. coli isolates were analyzed. B2 phylogenetic group was predominant, with high VF gene content and low antimicrobial resistance. Antimicrobial resistance diversity was observed in four patients with VAP. E. coli isolates from VAP patients were more frequently B2 isolates, with significantly greater VF gene content than lung colonization isolates. Among screened VF genes, iroN and sfa appeared important for lung infection. A very strong correlation ( R 2  = 0.99) was found between VF gene content and mortality in the mouse model. Conclusions This is the first study establishing antibioresistance and genotypic characteristics of E. coli isolates responsible for VAP in adult ICU patients. These isolates are highly virulent specific extraintestinal pathogenic E. coli strains expressing virulence factors, representing potential targets for new therapies.

Whole genome sequencing of Mycobacterium tuberculosis complex (MTBC) strains is a new and rapidly growing tool to obtain results regarding resistance, virulence factors and phylogeny of the strains. Bioinformatics tools presented as user-friendly and easy to use are available online. The objective of this work was to evaluate the performances of two bioinformatics tools, easily accessible on the internet, for the analysis of sequencing data of MTBC strains. Two hundred and twenty-seven MTBC strains isolated at the laboratory of the Avicenne Hospital between 2015 and 2021 were sequenced using Illumina®(USA) MiSeq technology. An analysis of the sequencing data was performed using the two tools Mykrobe and PhyResSE. Sequencing quality, resistance or susceptibility status and phylogeny were investigated for each strain. Genotypic resistance results were compared to the results obtained by phenotypic drug susceptibility testing performed in the hospital’s routine laboratory. Using the PhyResSE tool we found an average coverage of 98% against the reference strain H37Rv and an average depth of 119X. No information on sequencing quality was obtained with the Mykrobe tool. The concordance of each tool with the phenotypic method for determining susceptibility to first-line anti-tuberculosis drugs was 95%. Mykrobe and PhyResSE tools identified resistance to second-line anti-tuberculosis drugs in 5.3% and 5.7% of cases respectively. The sensitivity and specificity of each tool compared to the phenotypic method was respectively 70% and 98% for Mykrobe and 76% and 97% for PhyResSE. Finally, the two tools showed 99.5% agreement in lineage determination. The Mykrobe and PhyResSE bioinformatics tools were easy to use, fast and efficient. The Mykrobe tool had the advantage of being offline and its interface was more user-friendly. The use of these platforms depends on their accessibility and updating. However, their use is accessible to people not trained in bioinformatics and would allow a complementary approach to phenotypic methods for the study of MTBC strains.