Invasive group B Streptococcus infections in non-pregnant adults: a retrospective study, France, 2007–2019

Abstract

Objectives: Group B Streptococcus (GBS) (Streptococcus agalactiae) is a pathogen of growing importance in adults. The objective of this study was to describe the features of invasive infections by GBS in nonpregnant adults. Methods: GBS infections were reported to the national reference centre for streptococci. Clinical information was abstracted from questionnaires. Capsular typing, identification of the hypervirulent CC-17 clone, and antibiotic susceptibility testing were performed for all GBS isolates. Multi-locus sequence typing and assignment to clonal complexes (CCs) was performed on a representative sample of 324 isolates. Results: In total, 1960 GBS invasive infections were analysed from 2007 to 2019. The median age at onset was 71 years old (range 18e103). The main manifestation was bacteraemia without focus (54.5%). Meningitis was more frequent in patients under 40 (26/180, 14.4% versus 78/1780, 4.4%, p < 0.0001). Capsular types Ia, Ib, II, III and V accounted for 91.0% of the cases (1786/1960). CC-1, -10, -17, -19 and -23 accounted for 96.3% (312/324) of the cases. Capsular type III and CC-17 were overrepresented in meningitis (38/104, 36.5%, p < 0.001 and 22/104, 21.2%, p 0.01, respectively). All isolates were susceptible to blactam antibiotics. Resistance to erythromycin (32.7%) and clindamycin (26.3%) remained stable, whereas decreased susceptibility to fluoroquinolones increased, reaching 2.7% in 2019 (p for trend 0.002). Conclusions: This work highlights the susceptibility of the elderly to GBS infections and differences in the clinical manifestations according to the patients' age and GBS type. In agreement with worldwide reports on emerging multidrug-resistant GBS, it reinforces the need for a continued surveillance of GBS epidemiology.

Clustered Regularly Interspaced Short Palindromic Repeat Analysis of Clonal Complex 17 Serotype III Group B Streptococcus Strains Causing Neonatal Invasive Diseases

“…In addition, distinctive features of CRISPR loci were identified between different clonal complexes that are representative of different GBS strains [ 22 , 25 ]. It is well-known that the CC17/III GBS strain has emerged as the major pathogen causing neonatal invasive diseases and meningitis because this hypervirulent strain has specific virulence factors and adhesion molecules that can assist in invasion [ 26 , 27 , 28 ]. However, the clinical manifestations of all CC17/III GBS strains may vary greatly at presentation, as some of them present with fulminant sepsis and meningitis.…”

Genomic Traits Associated with Virulence and Antimicrobial Resistance of Invasive Group B Streptococcus Isolates with Reduced Penicillin Susceptibility from Elderly Adults

“… Streptococcus agalactiae , or group B Streptococcus (GBS), is recognized as the leading cause of neonatal invasive infections like sepsis and meningitis. However, an increasing incidence of invasive GBS infections in nonpregnant adults, particularly in elderly and immunocompromised individuals with underlying diseases like diabetes mellitus, has been noted in recent years, where skin and soft tissue infections, bacteremia, osteomyelitis, and urinary tract infections are the most common clinical manifestations ( 1 – 5 ). In adults over 65 years of age, GBS has predominantly been associated with primary bacteremia (28 to 60%), resulting in significant mortality (6.6 to 15.6%) ( 1 , 5 , 6 ).…”

Streptococcus agalactiae Infects Glial Cells and Invades the Central Nervous System via the Olfactory and Trigeminal Nerves

“…In the current study, we investigated whether S. agalactiae sequence type 17 (ST17); serotype III, which is epidemiologically the most relevant in neonatal ( Edmond et al, 2012 ) and adult ( Paveenkittiporn et al, 2020 ; Vuillemin et al, 2020 ) Group B streptococcal meningitis, can infect the brain via the olfactory and/or trigeminal nerves in mice. Because epithelial injury is associated with increased infection of the olfactory nerve, we also determined the effects of prior experimental injury to the nasal epithelium on S. agalactiae infection via this path.…”