title: A Whole-Genome Sequencing Approach To Study Cefoxitin-Resistant Salmonella enterica Serovar Heidelberg Isolates from Various Sources.
abstract: This study characterized cefoxitin-resistant and -susceptibleSalmonella entericaserovar Heidelberg strains from humans, abattoir poultry, and retail poultry to assess the molecular relationships of isolates from these sources in Québec in 2012. Isolates were collected as part of the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS). All isolates were subjected to antimicrobial susceptibility testing, PCR for CMY-2, pulsed-field gel electrophoresis (PFGE), and whole-genome sequencing (WGS). A total of 113SHeidelberg isolates from humans (n= 51), abattoir poultry (n= 18), and retail poultry (n= 44) were studied. All cefoxitin-resistant isolates (n= 65) were also resistant to amoxicillin-clavulanic acid, ampicillin, ceftiofur, and ceftriaxone, and all contained the CMY-2 gene. PFGE analysis showed that 111/113 (98.2%) isolates clustered together with ≥90% similarity. Core genome analysis using WGS identified 13 small clusters of isolates with 0 to 4 single nucleotide variations (SNVs), consisting of cefoxitin-resistant and -susceptible human, abattoir poultry, and retail poultry isolates. CMY-2 plasmids from cefoxitin-resistant isolates all belonged to incompatibility group I1. Analysis of IncI1 plasmid sequences revealed high identity (95 to 99%) to a previously described plasmid (pCVM29188_101) found inSalmonellaKentucky. When compared to pCVM29188_101, all sequenced cefoxitin-resistant isolates were found to carry 1 of 10 possible variant plasmids. Transmission ofSHeidelberg may be occurring between human, abattoir poultry, and retail poultry sources, and transmission of a common CMY-2 plasmid may be occurring amongSHeidelberg strains with variable genetic backgrounds.
authors.affiliation: Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada.|National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada.
authors.forename: Romaine
authors.initials: R
authors.lastname: Edirmanasinghe
authors.affiliation: Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Guelph, ON, Canada.
authors.forename: Rita
authors.initials: R
authors.lastname: Finley
authors.affiliation: Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Guelph, ON, Canada.
authors.forename: E Jane
authors.initials: EJ
authors.lastname: Parmley
authors.affiliation: Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Guelph, ON, Canada.
authors.forename: Brent P
authors.initials: BP
authors.lastname: Avery
authors.affiliation: Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Guelph, ON, Canada.
authors.forename: Carolee
authors.initials: C
authors.lastname: Carson
authors.affiliation: Institut national de santé publique du Québec, Montréal, QC, Canada.
authors.forename: Sadjia
authors.initials: S
authors.lastname: Bekal
authors.affiliation: Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada.|National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada.
authors.forename: George
authors.initials: G
authors.lastname: Golding
authors.affiliation: Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada Michael.Mulvey@phac-aspc.gc.ca.|National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Mulvey
mesh_terms: D019980:Amoxicillin-Potassium Clavulanate Combination / Q000494:pharmacology; D000667:Ampicillin / Q000494:pharmacology; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002170:Canada / Q000453:epidemiology; D002440:Cefoxitin / Q000494:pharmacology*; D002443:Ceftriaxone / Q000494:pharmacology; D002511:Cephalosporins / Q000494:pharmacology; D002645:Chickens; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D062665:Epidemiological Monitoring; D015870:Gene Expression; D016680:Genome, Bacterial; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D008460:Meat / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D010802:Phylogeny; D020641:Polymorphism, Single Nucleotide; D012480:Salmonella Infections / Q000453:epidemiology / Q000382:microbiology / Q000635:transmission; D019779:Salmonella enterica / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D002440:Cefoxitin; D019980:Amoxicillin-Potassium Clavulanate Combination; D002443:Ceftriaxone; D000667:Ampicillin; C053503:ceftiofur; C103022:beta-lactamase CMY-2; D001618:beta-Lactamases
keywords: Québec; Salmonella Heidelberg; beta-lactamase; cefoxitin; plasmid analysis; whole-genome sequencing