A Hunt for the Resistance of to Beta-Lactams.

Infections due to require prompt treatment using beta-lactam antibiotics. We used a collection of 81 isolates obtained between 1940 and 2001 from several countries. Whole genome sequencing showed the high heterogeneity of these isolates but allowed us to track the acquisition of beta-lactamase, which was first detected in 1980.

The rapid rebound of invasive meningococcal disease in France at the end of 2022.

Background: Invasive meningococcal disease (IMD) cases declined upon the implementation of non-pharmaceutical measures to control the COVID-19 pandemic. A rebound in IMD cases was feared upon easing these measures.

Methods: We conducted a retrospective descriptive study using the French National Reference Center Database for meningococci between 2015 and 2022.

Recent Evolution of Susceptibility to Beta-Lactams in .

Beta-lactams are the main antibiotics for the treatment of invasive meningococcal disease. However, reduced susceptibility to penicillin G is increasingly reported in and reduced susceptibility to third-generation cephalosporines (3GC) and the rare acquisition of ROB-1 beta-lactamase were also described. Modifications of penicillin-binding protein 2 (PBP2) encoded by the gene are the main described mechanism for the reduced susceptibility to penicillin and to other beta-lactams.

Characteristics of Meningococcal Invasive Disease in Neonates and Virulence of the Corresponding Isolates.

Background: The highest incidence of invasive meningococcal disease (IMD) is observed in infants. However, its prevalence in neonates (≤28 days of age) and the characteristics of the corresponding isolates are less described. This report aimed to analyze meningococcal isolates from neonates.

Evolution of strain coverage by the multicomponent meningococcal serogroup B vaccine (4CMenB) in France.

The 4CMenB, a protein-based vaccine, was licensed in Europe in 2013 against invasive meningococcal disease caused by serogroup B and is currently implemented in several countries although according to different national strategies. Isolate coverage estimation is required as vaccine-targeted antigens may vary among isolates over time. Several phenotypic and genotypic methods have been developed to predict strain coverage by scoring the expression and cross-reactivity of vaccine antigens using the Meningococcal Antigen Typing system (MATS), by the genetic correlation of alleles encoding these antigens and MATS expression data (gMATS) and by the Meningococcal Deduced Vaccine Antigen Reactivity (MenDeVAR).

Haemophilus influenzae type b (Hib) seroprevalence in France: impact of vaccination schedules.

Background: Haemophilus influenzae serotype b (Hib) conjugate vaccine was introduced in France in 1992 as a 3 + 1 scheme at 2, 3, and 4 months (primary vaccination) with a booster at the age of 16-18 months. The vaccination was simplified in 2013 to a 2 + 1 scheme at 2 and 4 months (primary immunization) and a booster at the age of 11 months. The coverage was 95.

4CMenB Immunization Induces Serum Bactericidal Antibodies Against Non-Serogroup B Meningococcal Strains in Adolescents.

Introduction: Invasive meningococcal disease (IMD) is an important public health concern. In developed countries, most IMD is caused by meningococcal serogroup B (MenB) and two protein-based MenB vaccines are currently available: the four-component vaccine 4CMenB (Bexsero, GSK) and the bivalent vaccine MenB-FHbp (Trumenba, Pfizer). Genes encoding the 4CMenB vaccine antigens are also present in strains belonging to other meningococcal serogroups.

Multicomponent meningococcal serogroup B vaccination elicits cross-reactive immunity in infants against genetically diverse serogroup C, W and Y invasive disease isolates.

Background: The multicomponent meningococcal serogroup B vaccine (4CMenB) is currently indicated for active immunization against invasive meningococcal disease caused by Neisseria meningitidis serogroup B (MenB). However, genes encoding the 4CMenB antigens are also variably present and expressed in strains belonging to other meningococcal serogroups. In this study, we evaluated the ability of antibodies raised by 4CMenB immunisation to induce complement-mediated bactericidal killing of non-MenB strains.

Analysis of Haemophilus species in patients with respiratory tract infections in Yaoundé, Cameroon.

Objectives: To identifyHaemophilus species and characterize antimicrobial susceptibility of isolates from patients with respiratory tract infections (RTIs) in Cameroon.

Methods: Isolates (n = 95) were from patients with RTIs obtained from two Hospitals in Yaoundé, Cameroon. Isolates were identified by biochemical assay, PCR-based method, MALDI-TOF and whole genome sequencing.

Strain coverage of Bexsero vaccine assessed by whole-genome sequencing over a cohort of invasive meningococci of serogroups B and W isolated in Switzerland.

Invasive meningococcal disease (IMD), caused by Neisseria meningitidis (Nm) strains, is a life-threatening but vaccine-preventable condition. Bexsero is a four-component vaccine that offers broad protection against Nm of serogroup B (NmB), particularly common in Europe. In Switzerland, Bexsero has not yet been licensed and no information is available concerning the predicted vaccine coverage on isolates of circulating Nm.

Genetic variability of Polish serogroup B meningococci (2010-2016) including the 4CMenB vaccine component genes.

Neisseria meningitidis serogroup B (MenB) has recently become the major cause of invasive meningococcal disease in Poland. Therefore, the purpose of this study was to characterize MenB isolates, responsible for invasive meningococcal disease in 2010-2016, by MLST and sequencing of genes encoding proteins used as 4CMenB vaccine antigens. Two methods of coverage estimation were performed: extrapolation of MATS results of Polish meningococci 2010-2011 (exMATS) and gMATS, which combines genotyping and MATS results.

Validation of a New Rapid Detection Test for Detection of Neisseria meningitidis A/C/W/X/Y Antigens in Cerebrospinal Fluid.

Meningococcal meningitis remains a life-threatening disease worldwide, with high prevalence in the sub-Saharan meningitis belt. A rapid diagnosis is crucial for implementing adapted antimicrobial treatment. We describe the performances of a new immunochromatographic test (MeningoSpeed, BioSpeedia, France) for detecting and grouping Cerebrospinal fluids (CSFs) were collected from 5 African countries and France.

High diversity of invasive Haemophilus influenzae isolates in France and the emergence of resistance to third generation cephalosporins by alteration of ftsI gene.

Background: Invasive infections due to Haemophilus influenzae are infrequent following the implementation of vaccination against H. influenzae of serotype b. However, their changing epidemiology may not be clear due to a lack of appropriate genotyping methods combined with antibiotic susceptibility analyses which do not discriminate invasive and non-invasive isolates.

Diagnosis of Meningococcal Infection Using Internally Controlled Multiplex Real-Time PCR.

Neisseria meningitidis (Nm) is a leading cause of invasive infections associated with high mortality and morbidity, notably meningitis and septicemia. Etiological rapid diagnosis is key for the preventive management of invasive meningococcal disease (IMD). However, conventional methods for diagnosis are time-consuming and could be hampered by the difficulties in culturing the isolates from clinical specimens especially due to early antibiotic treatment.

Phylogenetic relationships and regional spread of meningococcal strains in the meningitis belt, 2011-2016.

Background: Historically, the major cause of meningococcal epidemics in the meningitis belt of sub-Saharan Africa has been Neisseria meningitidis serogroup A (NmA), but the incidence has been substantially reduced since the introduction of a serogroup A conjugate vaccine starting in 2010. We performed whole-genome sequencing on isolates collected post-2010 to assess their phylogenetic relationships and inter-country transmission.

Methods: A total of 716 invasive meningococcal isolates collected between 2011 and 2016 from 11 meningitis belt countries were whole-genome sequenced for molecular characterization by the three WHO Collaborating Centers for Meningitis.

Characterization of meningococcal carriage isolates from Greece by whole genome sequencing: Implications for 4CMenB vaccine implementation.

Herd protection, resulting from the interruption of transmission and asymptomatic carriage, is an important element of the effectiveness of vaccines against the meningococcus. Whilst this has been well established for conjugate polysaccharide vaccines directed against the meningococcal capsule, two uncertainties surround the potential herd protection provided by the novel protein-based vaccines that are used in place of serogroup B (MenB) polysaccharide vaccines (i) the strain coverage of such vaccines against carried meningococci, which are highly diverse; and (ii) the generation of a protective immune response in the mucosa. These considerations are essential for realistic estimates of cost-effectiveness of new MenB vaccines.

Acquisition of Beta-Lactamase by Neisseria meningitidis through Possible Horizontal Gene Transfer.

We report the detection in France of a beta-lactamase-producing invasive meningococcal isolate. Whole-genome sequencing of the isolate revealed a ROB-1-type beta-lactamase gene that is frequently encountered in , suggesting horizontal transfer between isolates of these bacterial species. Beta-lactamases are exceptional in meningococci, with no reports for more than 2 decades.

Molecular Characterization of Invasive Isolates of Neisseria meningitidis in Casablanca, Morocco.

Meningococcal epidemiology may change unpredictably, and typing of isolates is crucial for the surveillance of invasive meningococcal disease (IMD). Few data are available regarding the meningococcal epidemiology in countries of North Africa. We aimed to explore invasive meningococcal isolates from the Casablanca region in Morocco.

Unusual Initial Abdominal Presentations of Invasive Meningococcal Disease.

Background: Invasive meningococcal disease (IMD) is recognized as septicemia and/or meningitis. However, early symptoms may vary and are frequently nonspecific. Early abdominal presentations have been increasingly described.

Clonal replacement and expansion among invasive meningococcal isolates of serogroup W in France.

Background: Neisseria meningitidis group W (NmW) belonging to the clonal complex ST-11 (NmW/cc11) spread in Europe and in France in 2000 and declined thereafter. In France, invasive meningococcal disease (IMD) due to NmW increased again in 2012 and thereafter since 2015. Several sub-lineages of NmW/cc11 are circulating worldwide with successive epidemic waves.

A cluster of invasive meningococcal disease (IMD) caused by Neisseria meningitidis serogroup W among university students, France, February to May 2017.

Between February and May 2017, two cases of invasive meningococcal disease caused by a new, rapidly expanding serogroup W meningococci variant were reported among students of an international university in Paris. Bacteriological investigations showed that isolates shared identical genotypic formula (W:P1.5,2:F1-1:cc11) and belonged to the South American/UK lineage.