Large Clusters of Invasive emm49 Group A Streptococcus Identified Within Arizona Health Care Facilities Through Statewide Genomic Surveillance System, 2019-2021

J Infect Dis. 2024 Sep 23;230(3):598-605. doi: 10.1093/infdis/jiae086.

Abstract

A statewide genomic surveillance system for invasive Group A Streptococcus was implemented in Arizona in June 2019, resulting in 1046 isolates being submitted for genomic analysis to characterize emm types and identify transmission clusters. Eleven of the 32 identified distinct emm types comprised >80% of samples, with 29.7% of all isolates being typed as emm49 (and its genetic derivative emm151). Phylogenetic analysis initially identified an emm49 genomic cluster of 4 isolates that rapidly expanded over subsequent months (June 2019 to February 2020). Public health investigations identified epidemiologic links with 3 different long-term care facilities, resulting in specific interventions. Unbiased genomic surveillance allowed for identification and response to clusters that would have otherwise remained undetected.

Keywords: emm types; clusters; genomic; group A Streptococcus; invasive; surveillance.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Antigens, Bacterial / genetics
  • Arizona / epidemiology
  • Bacterial Outer Membrane Proteins / genetics
  • Child
  • Child, Preschool
  • Epidemiological Monitoring
  • Female
  • Genome, Bacterial
  • Genomics
  • Health Facilities
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Middle Aged
  • Phylogeny*
  • Streptococcal Infections* / epidemiology
  • Streptococcal Infections* / microbiology
  • Streptococcus pyogenes* / classification
  • Streptococcus pyogenes* / genetics
  • Streptococcus pyogenes* / isolation & purification
  • Young Adult

Substances

  • Bacterial Outer Membrane Proteins
  • Antigens, Bacterial