Comparison of pharyngeal and invasive isolates of <i>Streptococcus pyogenes</i> by whole-genome sequencing in Toronto, Canada.

ABSTRACT: Invasive Group A streptococcal (iGAS) infections are rising in Canada and wordwide. The 2022-2023 Ontario iGAS season was among the highest recorded, a trend continuing in 2023-2024. We sequenced 38 invasive (blood) and 117 non-invasive (pharyngeal) Streptococcus pyogenes clinical isolates from Toronto (January-May 2023) to compare between the two cohorts and against published sequences to determine if any genomic changes accounted for the trend. Results demonstrated limited clustering with one small totally invasive cluster (emm49) with both invasive and non-invasive isolates represented across a diverse set of lineages. Non-invasive isolates were predominantly emm12 (70.1%), whereas invasive isolates included emm12 (26.32%), emm49 (23.68%), and emm1<

SUBMITTER: Zeppa JJ 

PROVIDER: S-EPMC11960128 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature