{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T01:11:52Z","timestamp":1790039512853,"version":"4.0.1"},"reference-count":20,"publisher":"Oxford University Press (OUP)","issue":"2","license":[{"start":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T00:00:00Z","timestamp":1768780800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"funder":[{"DOI":"10.13039\/100010318","name":"University of Manitoba","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100010318","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Microbiology Laboratory"},{"name":"Avir Pharma Inc."},{"name":"Iterum Therapeutics"},{"DOI":"10.13039\/501100015631","name":"Merck Canada Inc.","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100015631","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Paladin Labs"},{"DOI":"10.13039\/100004319","name":"Pfizer","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100004319","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100023517","name":"Sandoz Canada","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100023517","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Shionogi Inc."},{"name":"Sunovion Pharmaceuticals Canada Inc."},{"name":"Venatorx Pharmaceuticals Inc."},{"name":"Verity Pharmaceuticals"},{"name":"Xediton Pharmaceuticals Inc."},{"name":"Government of Canada Shared Priority Project"},{"name":"Genomics Research and Development Initiative, project GRDI-AMR-One-Health"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,1,19]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>VRE resistant to potential therapeutic agents such as linezolid are an increasing concern in Canada and worldwide. Infections produced by these isolates have limited treatment options and are associated with poor clinical outcomes. We report an isolate of vancomycin-resistant Enterococcus faecium (VREfm); identified through the Canadian surveillance program, CANWARD, which exhibited linezolid resistance (LVREfm); and carried the optrA and cfr(D) genes on a linear plasmid.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Antimicrobial susceptibility testing was performed by broth microdilution and MICs were interpreted by 2025 CLSI breakpoints. WGS was performed to characterize resistance determinants and the associated plasmid.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>In 2021, a single LVREfm isolate was recovered from a blood culture of a 67-year-old male patient admitted to an ICU. The isolate was XDR but remained susceptible dose dependent to daptomycin (MIC = 2\u2005mg\/L). MLST identified the isolate as ST817, a sequence type not commonly found in our national collection.<\/jats:p>\n                    <jats:p>Vancomycin resistance was mediated by the vanA gene cluster, while linezolid resistance determinants included optrA, cfr(D) and the 23S rRNA gene mutation, G2576T. Vancomycin and linezolid resistance genes were co-located on a linear plasmid that exhibited over 94% sequence identity to previously described linear plasmids from India and the USA. Notably, the plasmid also encoded four toxin\u2013antitoxin systems, potentially contributing to its stability and persistence.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>This case highlights the appearance of linezolid resistance in VRE mediated by linear plasmids in Canada and underscores the importance of ongoing genomic surveillance to track the dissemination of MDR determinants in clinical settings.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/jac\/dkaf478","type":"journal-article","created":{"date-parts":[[2025,12,13]],"date-time":"2025-12-13T13:00:40Z","timestamp":1765630840000},"source":"Crossref","is-referenced-by-count":4,"title":["<i>Enterococcus faecium<\/i>\n                    harbouring\n                    <i>vanA<\/i>\n                    ,\n                    <i>optrA<\/i>\n                    and\n                    <i>cfr(<\/i>\n                    D) on a linear plasmid in Canada: a CANWARD surveillance case"],"prefix":"10.1093","volume":"81","author":[{"given":"Melissa","family":"McCracken","sequence":"first","affiliation":[{"name":"National Microbiology Laboratory, Public Health Agency of Canada , 1015 Arlington Street, Winnipeg, Manitoba R3E 3M4 ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7914-9198","authenticated-orcid":false,"given":"Nicole","family":"Lerminiaux","sequence":"additional","affiliation":[{"name":"National Microbiology Laboratory, Public Health Agency of Canada , 1015 Arlington Street, Winnipeg, Manitoba R3E 3M4 ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5646-6454","authenticated-orcid":false,"given":"Heather J","family":"Adam","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology\/Infectious Diseases, Max Rady College of Medicine, University of Manitoba , Room 543-745 Bannatyne Avenue, Winnipeg, Manitoba R3E 0J9 ,","place":["Canada"]},{"name":"Clinical Microbiology, Diagnostic Services, Shared Health , MS673-820 Sherbrook Street, Winnipeg, Manitoba R3A 1R9 ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Melanie","family":"Baxter","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology\/Infectious Diseases, Max Rady College of Medicine, University of Manitoba , Room 543-745 Bannatyne Avenue, Winnipeg, Manitoba R3E 0J9 ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"James A","family":"Karlowsky","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology\/Infectious Diseases, Max Rady College of Medicine, University of Manitoba , Room 543-745 Bannatyne Avenue, Winnipeg, Manitoba R3E 0J9 ,","place":["Canada"]},{"name":"Clinical Microbiology, Diagnostic Services, Shared Health , MS673-820 Sherbrook Street, Winnipeg, Manitoba R3A 1R9 ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"George R","family":"Golding","sequence":"additional","affiliation":[{"name":"National Microbiology Laboratory, Public Health Agency of Canada , 1015 Arlington Street, Winnipeg, Manitoba R3E 3M4 ,","place":["Canada"]},{"name":"Department of Medical Microbiology\/Infectious Diseases, Max Rady College of Medicine, University of Manitoba , Room 543-745 Bannatyne Avenue, Winnipeg, Manitoba R3E 0J9 ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"George G","family":"Zhanel","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology\/Infectious Diseases, Max Rady College of Medicine, University of Manitoba , Room 543-745 Bannatyne Avenue, Winnipeg, Manitoba R3E 0J9 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