{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T03:17:14Z","timestamp":1790306234316,"version":"4.1.0"},"reference-count":38,"publisher":"Oxford University Press (OUP)","issue":"4","license":[{"start":{"date-parts":[[2025,8,19]],"date-time":"2025-08-19T00:00:00Z","timestamp":1755561600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100013873","name":"Government of Ontario","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100013873","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Research Institute of St Joseph's Healthcare"},{"name":"family of the late Mr David Braley"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,10,15]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>Serratia marcescens is an opportunistic AmpC \u03b2-lactamase-producing Enterobacterales associated with intensive care unit outbreaks, causing high morbidity and mortality. The spatiotemporal dynamics of Serratia species and their implications for hospital infection prevention and control remain understudied.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>We prospectively identified patient culture specimens in a multihospital academic healthcare system from 2022 to 2024. We included first-time isolates of S. marcescens identified via culture and confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Isolates underwent whole-genome sequencing on the Illumina NextSeq 2000 platform. We queried assembled genomes using the Comprehensive Antibiotic Resistance Database to identify resistance genes and predict resistomes. We constructed a maximum-likelihood phylogenetic tree using GTDB-Tk\u2013assigned taxonomies. We identified possible links between patients if there was a spatiotemporal overlap and the average nucleotide identity (ANI) of a sequence pair was &amp;gt; 99.0%. We collected relevant patient characteristics via retrospective chart review and analyzed data using descriptive statistics.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>Of 147 identified isolates, we included 125. Phenotypic testing suggested either inducible or derepressed AmpC expression in all isolates. Whole-genome sequencing found species-level discordance with MALDI-TOF MS in 64 (51.2%) isolates, suggesting the presence of multiple members of the recently described S. marcescens complex causing hospital- or community-associated infections. Only 1 isolate pair had a spatiotemporal link and ANI &amp;gt; 99.0%.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>Between-patient transmission of S. marcescens complex outside of outbreaks is likely rare. Current MALDI-TOF MS-based identification methods are insufficient to identify S. marcescens complex and laboratory reporting should be modified to report only to the level of the complex.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/infdis\/jiaf392","type":"journal-article","created":{"date-parts":[[2025,8,19]],"date-time":"2025-08-19T13:01:38Z","timestamp":1755608498000},"page":"e589-e600","source":"Crossref","is-referenced-by-count":4,"title":["Molecular Epidemiology of Clinical Infections Caused by <i>Serratia marcescens<\/i> Complex in a Tertiary Care Hospital System: Insights From Whole-Genome Sequencing"],"prefix":"10.1093","volume":"232","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2101-7701","authenticated-orcid":false,"given":"Adam S","family":"Komorowski","sequence":"first","affiliation":[{"name":"Department of Pathology and Molecular Medicine, McMaster University , Hamilton, Ontario ,","place":["Canada"]},{"name":"Department of Laboratory Medicine, Hamilton Health Sciences and St Joseph's Healthcare , Hamilton, Ontario ,","place":["Canada"]},{"name":"Department of Health Research Methodology, Evidence, and Impact, Faculty of Health Sciences, McMaster University , Hamilton, Ontario ,","place":["Canada"]},{"name":"Michael G. DeGroote Institute for Infectious Disease Research, McMaster University , Hamilton, Ontario ,","place":["Canada"]},{"name":"Research Institute of St Joseph's Healthcare Hamilton , St. Joseph\u2019s Healthcare, Hamilton, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0086-4995","authenticated-orcid":false,"given":"Michael G","family":"Surette","sequence":"additional","affiliation":[{"name":"Michael G. DeGroote Institute for Infectious Disease Research, McMaster University , Hamilton, Ontario ,","place":["Canada"]},{"name":"Department of Biochemistry and Biomedical Sciences, Faculty of Health Sciences, McMaster University , Hamilton, Ontario ,","place":["Canada"]},{"name":"Division of Gastroenterology, Department of Medicine, McMaster University , Hamilton, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1963-2484","authenticated-orcid":false,"given":"Laura","family":"Rossi","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Biomedical Sciences, Faculty of Health Sciences, McMaster University , Hamilton, Ontario ,","place":["Canada"]},{"name":"Division of Gastroenterology, Department of Medicine, McMaster University , Hamilton, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3245-1355","authenticated-orcid":false,"given":"Dominique","family":"Tertigas","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Biomedical Sciences, Faculty of Health Sciences, McMaster University , Hamilton, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark","family":"Gaskin","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Hamilton Health Sciences and St Joseph's Healthcare , Hamilton, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8773-3693","authenticated-orcid":false,"given":"Shahrokh","family":"Shekarriz","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Biomedical Sciences, Faculty of Health Sciences, McMaster University , Hamilton, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1142-3063","authenticated-orcid":false,"given":"Andrew G","family":"McArthur","sequence":"additional","affiliation":[{"name":"Michael G. DeGroote Institute for Infectious Disease Research, McMaster University , Hamilton, Ontario ,","place":["Canada"]},{"name":"Department of Biochemistry and Biomedical Sciences, Faculty of Health Sciences, McMaster University , Hamilton, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1655-3761","authenticated-orcid":false,"given":"Marek","family":"Smieja","sequence":"additional","affiliation":[{"name":"Department of Pathology and Molecular Medicine, McMaster University , Hamilton, Ontario ,","place":["Canada"]},{"name":"Department of Laboratory Medicine, Hamilton Health Sciences and St Joseph's Healthcare , Hamilton, Ontario ,","place":["Canada"]},{"name":"Department of Health Research Methodology, Evidence, and Impact, Faculty of Health Sciences, McMaster University , Hamilton, Ontario ,","place":["Canada"]},{"name":"Michael G. DeGroote Institute for Infectious Disease Research, McMaster University , Hamilton, Ontario ,","place":["Canada"]},{"name":"Research Institute of St Joseph's Healthcare Hamilton , St. Joseph\u2019s Healthcare, Hamilton, Ontario ,","place":["Canada"]},{"name":"Division of Infectious Diseases, Department of Medicine, McMaster University , Hamilton, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4337-1613","authenticated-orcid":false,"given":"Dominik","family":"Mertz","sequence":"additional","affiliation":[{"name":"Department of Health Research Methodology, Evidence, and Impact, Faculty of Health Sciences, McMaster University , Hamilton, Ontario ,","place":["Canada"]},{"name":"Michael G. DeGroote Institute for Infectious Disease Research, McMaster University , Hamilton, Ontario ,","place":["Canada"]},{"name":"Division of Infectious Diseases, Department of Medicine, McMaster University , Hamilton, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2025,8,19]]},"reference":[{"key":"2025101515150835300_jiaf392-B1","doi-asserted-by":"crossref","first-page":"5195","DOI":"10.1038\/s41467-022-32929-2","article-title":"The genus Serratia revisited by genomics","volume":"13","author":"Williams","year":"2022","journal-title":"Nat Commun"},{"key":"2025101515150835300_jiaf392-B2","doi-asserted-by":"crossref","first-page":"610","DOI":"10.3390\/ijerph16040610","article-title":"Serratia marcescens infections in neonatal intensive care units (NICUs)","volume":"16","author":"Cristina","year":"2019","journal-title":"Int J Environ Res Public 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