{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T11:21:21Z","timestamp":1785410481068,"version":"3.56.0"},"reference-count":41,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T00:00:00Z","timestamp":1776124800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council of Canada","doi-asserted-by":"publisher","award":["2022-04223"],"award-info":[{"award-number":["2022-04223"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]},{"award":["2022-04223"],"award-info":[{"award-number":["2022-04223"]}],"id":[{"id":"https:\/\/ror.org\/01h531d29","id-type":"ROR","asserted-by":"publisher"}]},{"name":"GREMIP, Faculty of Veterinary Medicine, University de Montreal and from CRIPA"},{"name":"Agria Foundation"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Streptococcus dysgalactiae subsp. equisimilis (SDSE) is an emerging cause of invasive disease, yet contemporary genomic data from Canada remain scarce. We investigated 56 cases of invasive SDSE infection identified between 2018 and 2022 in two major tertiary care teaching hospitals in Toronto, Ontario, and characterized 49 corresponding isolates by whole-genome sequencing. Nearly three-quarters of infections were caused by the globally expanding ST20 emm type stG62647 lineage. Patients infected with this lineage were significantly older than those infected with non-ST20 lineages across both bloodstream and non-blood infections. Core-genome phylogenetic analysis revealed a highly clonal ST20 cluster, although two isolates had divergent emm types suggesting recombination at the emm locus. Non-ST20 lineages were numerically smaller and genetically more heterogeneous, including distinct sublineages within ST3 and ST34. All isolates were susceptible to \u03b2-lactams and vancomycin. Resistance to tetracycline, erythromycin, and clindamycin was detected in a subset of isolates and was associated with genes tetM, tetO, ermA, ermB, and msrD. Several antimicrobial resistance determinants were located on mobile genetic elements, including integrative and conjugative elements. Our findings provide a contemporary genomic view of invasive SDSE in Toronto, highlighting the dominance of the ST20 stG62647 lineage in agreement with recent global observations.<\/jats:p>","DOI":"10.3390\/microorganisms14040878","type":"journal-article","created":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T08:14:17Z","timestamp":1776154457000},"page":"878","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Dominance of the ST20 stG62647 Lineage Among Invasive Streptococcus dysgalactiae subsp. equisimilis Infections in Toronto, Canada"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-5165-6966","authenticated-orcid":false,"given":"Kayleigh","family":"Gauvin","sequence":"first","affiliation":[{"name":"GREMIP and CRIPA, Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, QC J2S 2M2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-1063-7983","authenticated-orcid":false,"given":"Kevin","family":"Li","sequence":"additional","affiliation":[{"name":"GREMIP and CRIPA, Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, QC J2S 2M2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-1181-7419","authenticated-orcid":false,"given":"Fengyang","family":"Hsu","sequence":"additional","affiliation":[{"name":"GREMIP and CRIPA, Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, QC J2S 2M2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5647-6137","authenticated-orcid":false,"given":"Allison","family":"McGeer","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Sinai Health System, Toronto, ON M5G 1X5, Canada"},{"name":"Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 3K3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9553-3798","authenticated-orcid":false,"given":"Nahuel","family":"Fittipaldi","sequence":"additional","affiliation":[{"name":"GREMIP and CRIPA, Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, QC J2S 2M2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1128\/JCM.05900-11","article-title":"Delineation of Streptococcus dysgalactiae, its subspecies, and its clinical and phylogenetic relationship to Streptococcus pyogenes","volume":"50","author":"Jensen","year":"2012","journal-title":"J. Clin. Microbiol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"528","DOI":"10.3201\/eid2903.221060","article-title":"Clonal Expansion of Multidrug-Resistant Streptococcus dysgalactiae Subspecies equisimilis Causing Bacteremia, Japan, 2005\u20132021","volume":"29","author":"Shinohara","year":"2023","journal-title":"Emerg. Infect. Dis."},{"key":"ref_3","first-page":"279","article-title":"Molecular characterization of invasive Streptococcus dysgalactiae subsp. equisimilis. Multicenter study: Argentina 2011\u20132012","volume":"48","author":"Traverso","year":"2016","journal-title":"Rev. Argent. Microbiol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1543","DOI":"10.3201\/eid2508.181758","article-title":"Emergent Invasive Group A Streptococcus dysgalactiae subsp. equisimilis, United States, 2015\u20132018","volume":"25","author":"Chochua","year":"2019","journal-title":"Emerg. Infect. Dis."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"575","DOI":"10.3109\/23744235.2015.1043940","article-title":"Matrix-assisted laser desorption\/ionization-time of flight mass spectrometry identification of large colony beta-hemolytic streptococci containing Lancefield groups A, C, and G","volume":"47","author":"Jensen","year":"2015","journal-title":"Infect. Dis."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"7589","DOI":"10.1038\/s41598-017-08162-z","article-title":"Emergence of a Streptococcus dysgalactiae subspecies equisimilis stG62647-lineage associated with severe clinical manifestations","volume":"7","author":"Oppegaard","year":"2017","journal-title":"Sci. Rep."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1442","DOI":"10.1086\/516780","article-title":"Virulence profiling of Streptococcus dysgalactiae subspecies equisimilis isolated from infected humans reveals 2 distinct genetic lineages that do not segregate with their phenotypes or propensity to cause diseases","volume":"44","author":"Davies","year":"2007","journal-title":"Clin. Infect. Dis."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"766","DOI":"10.1086\/605085","article-title":"Human infections due to Streptococcus dysgalactiae subspecies equisimilis","volume":"49","author":"Brandt","year":"2009","journal-title":"Clin. Infect. Dis."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"3477","DOI":"10.1038\/s41467-024-47816-1","article-title":"Overlapping Streptococcus pyogenes and Streptococcus dysgalactiae subspecies equisimilis household transmission and mobile genetic element exchange","volume":"15","author":"Xie","year":"2024","journal-title":"Nat. Commun."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"e0455022","DOI":"10.1128\/spectrum.04550-22","article-title":"Analysis of the Genomics and Mouse Virulence of an Emergent Clone of Streptococcus dysgalactiae Subspecies equisimilis","volume":"11","author":"Beres","year":"2023","journal-title":"Microbiol. Spectr."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Itzek, A., Wei\u00dfbach, V., Meintrup, D., Rie\u00df, B., van der Linden, M., and Borgmann, S. (2023). Epidemiological and Clinical Features of Streptococcus dysgalactiae ssp. equisimilis stG62647 and Other emm Types in Germany. Pathogens, 12.","DOI":"10.3390\/pathogens12040589"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"819","DOI":"10.1007\/s10096-023-04607-8","article-title":"Incidence, seasonal pattern, and clinical manifestations of Streptococcus dysgalactiae subspecies equisimilis bacteremia; a population-based study","volume":"42","author":"Nevanlinna","year":"2023","journal-title":"Eur. J. Clin. Microbiol. Infect. Dis."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"4739","DOI":"10.2147\/IDR.S279157","article-title":"Beta-Haemolytic Group A, C and G Streptococcal Infections in Southern Hungary: A 10-Year Population-Based Retrospective Survey (2008\u20132017) and a Review of the Literature","volume":"13","year":"2020","journal-title":"Infect. Drug Resist."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1303","DOI":"10.1007\/s10096-014-2092-0","article-title":"Streptococcus dysgalactiae subsp. equisimilis bacteremia: An emerging infection","volume":"33","author":"Rantala","year":"2014","journal-title":"Eur. J. Clin. Microbiol. Infect. Dis."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"e0368325","DOI":"10.1128\/spectrum.03683-25","article-title":"Genomic and patient epidemiology of Streptococcus dysgalactiae subspecies equisimilis in Houston, Texas","volume":"14","author":"Pouga","year":"2026","journal-title":"Microbiol. Spectr."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"211","DOI":"10.1016\/j.ijid.2014.03.1376","article-title":"Changing trends in \u03b2-hemolytic streptococcal bacteremia in Manitoba, Canada: 2007\u20132012","volume":"28","author":"Schwartz","year":"2014","journal-title":"Int. J. Infect. Dis."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1079","DOI":"10.3201\/eid2307.161259","article-title":"Clonal Clusters and Virulence Factors of Group C and G Streptococcus Causing Severe Infections, Manitoba, Canada, 2012\u20132014","volume":"23","author":"Lother","year":"2017","journal-title":"Emerg. Infect. Dis."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"613","DOI":"10.1128\/CMR.15.4.613-630.2002","article-title":"What happened to the streptococci: Overview of taxonomic and nomenclature changes","volume":"15","author":"Facklam","year":"2002","journal-title":"Clin. Microbiol. Rev."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"2815","DOI":"10.1038\/s41596-022-00738-y","article-title":"Metagenome analysis using the Kraken software suite","volume":"17","author":"Lu","year":"2022","journal-title":"Nat. Protoc."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"90","DOI":"10.1186\/s13073-014-0090-6","article-title":"SRST2: Rapid genomic surveillance for public health and hospital microbiology labs","volume":"6","author":"Inouye","year":"2014","journal-title":"Genome Med."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1644","DOI":"10.1093\/gbe\/evt117","article-title":"Complete genome sequence of Streptococcus dysgalactiae subsp. equisimilis 167 carrying Lancefield group C antigen and comparative genomics of S. dysgalactiae subsp. equisimilis strains","volume":"5","author":"Watanabe","year":"2013","journal-title":"Genome Biol. Evol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"587","DOI":"10.1093\/bioinformatics\/btu661","article-title":"A5-miseq: An updated pipeline to assemble microbial genomes from Illumina MiSeq data","volume":"31","author":"Coil","year":"2015","journal-title":"Bioinformatics"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2068","DOI":"10.1093\/bioinformatics\/btu153","article-title":"Prokka: Rapid prokaryotic genome annotation","volume":"30","author":"Seemann","year":"2014","journal-title":"Bioinformatics"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"124","DOI":"10.12688\/wellcomeopenres.14826.1","article-title":"Open-access bacterial population genomics: BIGSdb software, the PubMLST.org website and their applications","volume":"3","author":"Jolley","year":"2018","journal-title":"Wellcome Open Res."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1871","DOI":"10.1128\/JCM.00029-14","article-title":"Deriving group A Streptococcus typing information from short-read whole-genome sequencing data","volume":"52","author":"Athey","year":"2014","journal-title":"J. Clin. Microbiol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"D690","DOI":"10.1093\/nar\/gkac920","article-title":"CARD 2023: Expanded curation, support for machine learning, and resistome prediction at the Comprehensive Antibiotic Resistance Database","volume":"51","author":"Alcock","year":"2023","journal-title":"Nucleic Acids Res."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"3895","DOI":"10.1128\/AAC.02412-14","article-title":"In silico detection and typing of plasmids using PlasmidFinder and plasmid multilocus sequence typing","volume":"58","author":"Carattoli","year":"2014","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"lqac079","DOI":"10.1093\/nargab\/lqac079","article-title":"ICEscreen: A tool to detect Firmicute ICEs and IMEs, isolated or enclosed in composite structures","volume":"4","author":"Lao","year":"2022","journal-title":"NAR Genom. Bioinform."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"236","DOI":"10.1111\/j.1574-695X.2008.00469.x","article-title":"Superantigen gene profile diversity among clinical group A streptococcal isolates","volume":"54","author":"Maripuu","year":"2008","journal-title":"FEMS Immunol. Med. Microbiol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"842","DOI":"10.1128\/JCM.01312-09","article-title":"Streptococcus pyogenes isolates causing severe infections in Norway in 2006 to 2007: Emm types, multilocus sequence types, and superantigen profiles","volume":"48","author":"Meisal","year":"2010","journal-title":"J. Clin. Microbiol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1589","DOI":"10.1046\/j.1365-2958.2003.03411.x","article-title":"Streptococcus dysgalactiae-derived mitogen (SDM), a novel bacterial superantigen: Characterization of its biological activity and predicted tertiary structure","volume":"47","author":"Zhao","year":"2003","journal-title":"Mol. Microbiol."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Price, M.N., Dehal, P.S., and Arkin, A.P. (2010). FastTree 2--approximately maximum-likelihood trees for large alignments. PLoS ONE, 5.","DOI":"10.1371\/journal.pone.0009490"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"3041","DOI":"10.1093\/molbev\/msy194","article-title":"Two Methods for Mapping and Visualizing Associated Data on Phylogeny Using Ggtree","volume":"35","author":"Yu","year":"2018","journal-title":"Mol. Biol. Evol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"493","DOI":"10.1093\/ajcp\/45.4_ts.493","article-title":"Antibiotic susceptibility testing by a standardized single disk method","volume":"45","author":"Bauer","year":"1966","journal-title":"Am. J. Clin. Pathol."},{"key":"ref_35","unstructured":"(2024). Performance Standards for Antimicrobial Susceptibility Testing (Standard No. CLSI M100)."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1016\/j.diagmicrobio.2011.07.010","article-title":"Identification and characterization of plasmid-borne erm(T) macrolide resistance in group B and group A Streptococcus","volume":"71","author":"DiPersio","year":"2011","journal-title":"Diagn. Microbiol. Infect. Dis."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"O216","DOI":"10.1111\/1469-0691.12378","article-title":"Nationwide laboratory-based surveillance of invasive beta-haemolytic streptococci in Denmark from 2005 to 2011","volume":"20","author":"Lambertsen","year":"2014","journal-title":"Clin. Microbiol. Infect."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"e0257824","DOI":"10.1128\/mbio.02578-24","article-title":"Integrative genomic, virulence, and transcriptomic analysis of emergent Streptococcus dysgalactiae subspecies equisimilis (SDSE) emm type stG62647 isolates causing human infections","volume":"15","author":"Eraso","year":"2024","journal-title":"mBio"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"3376","DOI":"10.1093\/jac\/dkw320","article-title":"Description and characterization of a penicillin-resistant Streptococcus dysgalactiae subsp. equisimilis clone isolated from blood in three epidemiologically linked patients","volume":"71","author":"Fuursted","year":"2016","journal-title":"J. Antimicrob. Chemother."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"44","DOI":"10.1038\/s44259-024-00062-3","article-title":"Regulation of erm(T) MLS(B) phenotype expression in the emergent emm92 type group A Streptococcus","volume":"2","author":"Powell","year":"2024","journal-title":"NPJ Antimicrob. Resist."},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Li, X.Y., Yu, R., Xu, C., Shang, Y., Li, D., and Du, X.D. (2022). A Small Multihost Plasmid Carrying erm(T) Identified in Enterococcus faecalis. Front. Vet. Sci., 9.","DOI":"10.3389\/fvets.2022.850466"}],"container-title":["Microorganisms"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2607\/14\/4\/878\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T08:34:22Z","timestamp":1776155662000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2607\/14\/4\/878"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,14]]},"references-count":41,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2026,4]]}},"alternative-id":["microorganisms14040878"],"URL":"https:\/\/doi.org\/10.3390\/microorganisms14040878","relation":{},"ISSN":["2076-2607"],"issn-type":[{"value":"2076-2607","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,14]]}}}