Proximity to human settlement is directly related to carriage of critically important antimicrobial-resistant Escherichia coli and Klebsiella pneumoniae in Silver Gulls

Shewli Mukerji; Shafi Sahibzada; Rebecca Abraham; Marc Stegger; David Jordan; David J Hampson; Mark O'Dea; Terence Lee; Sam Abraham

doi:10.1016/j.vetmic.2023.109702

Proximity to human settlement is directly related to carriage of critically important antimicrobial-resistant Escherichia coli and Klebsiella pneumoniae in Silver Gulls

Vet Microbiol. 2023 May:280:109702. doi: 10.1016/j.vetmic.2023.109702. Epub 2023 Feb 17.

Authors

Shewli Mukerji¹, Shafi Sahibzada², Rebecca Abraham², Marc Stegger³, David Jordan⁴, David J Hampson², Mark O'Dea², Terence Lee², Sam Abraham⁵

Affiliations

¹ Antimicrobial Resistance and Infectious Diseases Laboratory, Harry Butler Institute, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia; School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy Campus, South Australia 5371, Australia.
² Antimicrobial Resistance and Infectious Diseases Laboratory, Harry Butler Institute, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia.
³ Antimicrobial Resistance and Infectious Diseases Laboratory, Harry Butler Institute, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia; Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark.
⁴ Antimicrobial Resistance and Infectious Diseases Laboratory, Harry Butler Institute, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia; New South Wales Department of Primary Industries, Wollongbar, New South Wales, Australia.
⁵ Antimicrobial Resistance and Infectious Diseases Laboratory, Harry Butler Institute, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia. Electronic address: s.abraham@murdoch.edu.au.

PMID: 36848814
DOI: 10.1016/j.vetmic.2023.109702

Abstract

Human population and activities play an important role in dissemination of antimicrobial resistant bacteria. This study investigated the relationship between carriage rates of critically important antimicrobial-resistant (CIA-R) Escherichia coli and Klebsiella pneumoniae by Silver Gulls and their proximity to human populations. Faecal swabs (n = 229) were collected from Silver Gulls across 10 southern coastline locations in Western Australia (WA) traversing 650 kms. The sampling locations included main town centres and remote areas. Fluoroquinolone and extended-spectrum cephalosporin-resistant E. coli and K. pneumoniae were isolated and tested for antimicrobial sensitivity. Genome sequencing was performed on n = 40 subset out of 98 E. coli and n = 14 subset out of 27 K. pneumoniae isolates to validate phenotypic resistance profiles and determine the molecular characteristics of strains. CIA-R E. coli and K. pneumoniae were detected in 69 (30.1 %) and 20 (8.73 %) of the faecal swabs respectively. Two large urban locations tested positive for CIA-R E. coli (frequency ranging from 34.3 % to 84.3 %), and/or for CIA-R K. pneumoniae (frequency ranging from 12.5 % to 50.0 %). A small number of CIA-R E. coli (3/31, 9.7 %) were identified at a small tourist town, but no CIA-R bacteria were recovered from gulls at remote sites. Commonly detected E. coli sequence types (STs) included ST131 (12.5 %) and ST1193 (10.0 %). Five K. pneumoniae STs were detected which included ST4568, ST6, ST485, ST967 and ST307. Resistance genes including bla_CTX-M-3, bla_CTX-M-15 and bla_CTX-M-27 were identified in both bacterial species. High-level colonisation of CIA-R E. coli and K. pneumoniae in Silver Gulls in and around urban areas compared to remote locations substantiates that anthropogenic activities are strongly associated with acquisition of resistant bacteria by gulls.

Keywords: Critically important antimicrobial; E. coli; Human population; K. pneumoniae; Proximity; Resistance; Silver Gulls.

MeSH terms

Animals
Anti-Bacterial Agents / pharmacology
Anti-Infective Agents*
Charadriiformes* / microbiology
Escherichia coli
Escherichia coli Infections* / epidemiology
Escherichia coli Infections* / microbiology
Escherichia coli Infections* / veterinary
Humans
Klebsiella Infections* / epidemiology
Klebsiella Infections* / microbiology
Klebsiella Infections* / veterinary
Klebsiella pneumoniae / genetics
Microbial Sensitivity Tests / veterinary
beta-Lactamases / genetics

Substances

Anti-Infective Agents
beta-Lactamases
Anti-Bacterial Agents