AUTHOR=Jones Sandra , Newton Peter , Payne Matthew , Furfaro Lucy 

TITLE=Epidemiology, Antimicrobial Resistance, and Virulence Determinants of Group B Streptococcus in an Australian Setting

JOURNAL=Frontiers in Microbiology

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.839079

DOI=10.3389/fmicb.2022.839079

ISSN=1664-302X

ABSTRACT=Streptococcus agalactiae (group B Streptococcus [GBS]) is a major neonatal pathogen and also causes invasive disease in non-pregnant adults.  100 GBS isolates (50 causing invasive disease, 50 colonising pregnant women) were characterized using capsular serotyping by latex agglutination, antimicrobial susceptibility testing and whole genome sequencing (WGS).  100% of isolates were susceptible to penicillin, 32% were resistant to clindamycin and 2 isolates had reduced susceptibility to ceftriaxone (MIC 0.75 mg/L) and were found to have unique alleles at pbp2X and pbp1A.  Capsular serotypes Ia (18%), III (18%), Ib (14%), V (12%) and VI (11%) were most common and comparison of latex agglutination and capsular genotyping by WGS showed 71% agreement.  15% of isolates correlated to capsular genotypes VI – VIII by WGS, indicating that a significant proportion may not be targeted by the proposed pentavalent vaccine (including types Ia, Ib, II, III, V) under development.  WGS is a useful aid in GBS surveillance and shows correlation to phenotypic serotyping and antimicrobial susceptibility data.