title: Emergence and spread of two distinct clonal groups of multidrug-resistant Escherichia coli in a veterinary teaching hospital in Australia.
abstract: Multidrug-resistant Escherichia coli (MDREC) expressing AmpC beta-lactamases have emerged as a cause of opportunistic infections in dogs. Following a cluster of extraintestinal infections caused by two distinct clonal groups (CGs) of bla(CMY)-producing MDREC, a 12-month infection control study was undertaken at a veterinary teaching hospital in Brisbane, Australia. Swabs from the rectum of hospitalized dogs (n=780), hospital staff (n=16) and the hospital environment (n=220) were plated onto selective agar to obtain multidrug-resistant (MDR) coliforms. These were then tested by multiplex PCR for E. coli uspA, bla(CMY) and the class 1 integron-associated dfrA17-aadA5 gene cassette for rapid identification of MDREC CG 1 (positive for all three genes) and CG 2 (positive for uspA and bla(CMY) only). A total of 16.5 % of the dog rectal swabs and 4.1% of the hospital environmental swabs yielded MDREC, and on the basis of multiplex PCR, PFGE and plasmid profiling, these were confirmed to belong to either CG 1 or CG 2. Both CG 1 and CG 2 isolates were obtained from clinical cases of extraintestinal infection and rectal swabs from hospitalized dogs over the same period of time, whereas only CG 1 isolates were obtained from the hospital environment. Both CGs were prevalent during the first 6 months, but only CG 2 was isolated during the second 6 months of the study. Two isolates obtained from rectal swabs of staff working in the hospital belonged to CG 2, with one of the isolates possessing the same REDP as nine isolates from dogs, including six isolates associated with cases of extraintestinal infection. CG 1 isolates belonged to E. coli serotypes O162 : H-, OR : H- or Ont : H-, whereas CG 2 isolates belonged to O153 : HR, OR : HR or OR : H34. These results confirm that in this particular outbreak, canine MDREC were highly clonal and CG 2 MDREC may colonize both humans and dogs.
authors.affiliation: Medical Faculty of the Christian University of Indonesia (FK-UKI), Cawang Atas, Jakarta, Indonesia.|School of Veterinary Science, University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: Hanna E
authors.initials: HE
authors.lastname: Sidjabat
authors.affiliation: School of Veterinary Science, University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: Kirsty M
authors.initials: KM
authors.lastname: Townsend
authors.affiliation: School of Veterinary Science, University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Lorentzen
authors.affiliation: Food Science Australia, Tingalpa DC, QLD 4173, Australia.
authors.forename: Kari S
authors.initials: KS
authors.lastname: Gobius
authors.affiliation: Food Science Australia, Tingalpa DC, QLD 4173, Australia.
authors.forename: Narelle
authors.initials: N
authors.lastname: Fegan
authors.affiliation: Immunology and Microbiology, Elizabeth Macarthur Agricultural Institute, PMB 8, Camden, NSW 2570, Australia.
authors.forename: James J-C
authors.initials: JJ
authors.lastname: Chin
authors.affiliation: Microbiology Diagnostic Unit, Public Health Laboratory, Department of Microbiology and Immunology, University of Melbourne, Royal Parade, Parkville, VIC 3052, Australia.
authors.forename: Karl A
authors.initials: KA
authors.lastname: Bettelheim
authors.affiliation: Center for Research in Anti-Infectives and Biotechnology, Department of Medical Microbiology and Immunology, School of Medicine, Creighton University, 2500 California Plaza, Omaha, NE 68178, USA.
authors.forename: Nancy D
authors.initials: ND
authors.lastname: Hanson
authors.affiliation: School of Veterinary Science, University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: John C
authors.initials: JC
authors.lastname: Bensink
authors.affiliation: School of Veterinary Science, University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: Darren J
authors.initials: DJ
authors.lastname: Trott
mesh_terms: D000818:Animals; D001315:Australia / Q000453:epidemiology; D001426:Bacterial Proteins / Q000235:genetics; D002999:Clone Cells / Q000145:classification / Q000187:drug effects / Q000378:metabolism; D004283:Dog Diseases / Q000453:epidemiology* / Q000382:microbiology; D004285:Dogs; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D004784:Environmental Monitoring; D062665:Epidemiological Monitoring; D004926:Escherichia coli / Q000145:classification* / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D006360:Heat-Shock Proteins / Q000235:genetics; D006762:Hospitals, Animal; D006784:Hospitals, Teaching; D006801:Humans; D032023:Integrons / Q000235:genetics; D017720:Molecular Epidemiology; D010564:Personnel, Hospital; D016133:Polymerase Chain Reaction; D012007:Rectum / Q000382:microbiology; D012703:Serotyping; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D006360:Heat-Shock Proteins; C078564:universal stress protein A, Bacteria; D001618:beta-Lactamases