title: Genetic Structure and Antimicrobial Resistance of Escherichia coli and Cryptic Clades in Birds with Diverse Human Associations.
abstract: The manner and extent to which birds associate with humans may influence the genetic attributes and antimicrobial resistance of their commensal Escherichia communities through strain transmission and altered selection pressures. In this study, we determined whether the distribution of the different Escherichia coli phylogenetic groups and cryptic clades, the occurrence of 49 virulence associated genes, and/or the prevalence of resistance to 12 antimicrobials differed between four groups of birds from Australia with contrasting types of human association. We found that birds sampled in suburban and wilderness areas had similar Escherichia communities. The Escherichia communities of backyard domestic poultry were phylogenetically distinct from the Escherichia communities sourced from all other birds, with a large proportion (46%) of poultry strains belonging to phylogenetic group A and a significant minority (17%) belonging to the cryptic clades. Wild birds sampled from veterinary and wildlife rehabilitation centers (in-care birds) carried Escherichia isolates that possessed particular virulence-associated genes more often than Escherichia isolates from birds sampled in suburban and wilderness areas. The Escherichia isolates from both the backyard poultry and in-care birds were more likely to be multidrug resistant than the Escherichia isolates from wild birds. We also detected a multidrug-resistant E. coli strain circulating in a wildlife rehabilitation center, reinforcing the importance of adequate hygiene practices when handling and caring for wildlife. We suggest that the relatively high frequency of antimicrobial resistance in the in-care birds and backyard poultry is due primarily to the use of antimicrobials in these animals, and we recommend that the treatment protocols used for these birds be reviewed.
authors.affiliation: Evolution, Ecology and Genetics, Research School of Biology, The Australian National University, Acton, Australian Capital Territory, Australia.
authors.forename: Michaela D J
authors.initials: MD
authors.lastname: Blyton
authors.affiliation: Evolution, Ecology and Genetics, Research School of Biology, The Australian National University, Acton, Australian Capital Territory, Australia.
authors.forename: Hongfei
authors.initials: H
authors.lastname: Pi
authors.affiliation: Evolution, Ecology and Genetics, Research School of Biology, The Australian National University, Acton, Australian Capital Territory, Australia.
authors.forename: Belinda
authors.initials: B
authors.lastname: Vangchhia
authors.affiliation: School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, Australia.
authors.forename: Sam
authors.initials: S
authors.lastname: Abraham
authors.affiliation: School of Animal and Veterinary Science, University of Adelaide, Roseworthy, South Australia, Australia.
authors.forename: Darren J
authors.initials: DJ
authors.lastname: Trott
authors.affiliation: VA Medical Center and Department of Medicine, University of Minnesota, Infectious Diseases, Minneapolis, Minnesota, USA.
authors.forename: James R
authors.initials: JR
authors.lastname: Johnson
authors.affiliation: Evolution, Ecology and Genetics, Research School of Biology, The Australian National University, Acton, Australian Capital Territory, Australia David.Gordon@anu.edu.au.
authors.forename: David M
authors.initials: DM
authors.lastname: Gordon
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001315:Australia / Q000453:epidemiology; D001717:Birds / Q000382:microbiology*; D002353:Carrier State / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000145:classification* / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D017720:Molecular Epidemiology; D010802:Phylogeny; D037521:Virulence Factors / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D037521:Virulence Factors