Urban Wildlife Crisis: Australian Silver Gull Is a Bystander Host to Widespread Clinical Antibiotic Resistance

• Main Authors: Bitar, I. (Author), Djordjevic, S.P (Author), Dolejska, M. (Author), Jamborova, I. (Author), Literak, I. (Author), Nesporova, K. (Author), Tarabai, H. (Author), Wyrsch, E.R (Author)
• Format: Article
• Language: English
• Published: American Society for Microbiology 2022
• Subjects: AMR; Escherichia coli; genomics; wildlife
• Online Access: View Fulltext in Publisher

 The Australian silver gull is an urban-adapted species that frequents anthropogenic waste sites. The enterobacterial flora of synanthropic birds often carries antibiotic resistance genes. Whole-genome sequence analyses of 425 Escherichia coli isolates from cloacal swabs of chicks inhabiting three coastal sites in New South Wales, Australia, cultured on media supplemented with meropenem, cefotaxime, or ciprofloxacin are reported. Phylogenetically, over 170 antibiotic-resistant lineages from 96 sequence types (STs) representing all major phylogroups were identified. Remarkably, 25 STs hosted the carbapenemase gene blaIMP-4, sourced only from Five Islands. Class 1 integrons carrying blaIMP and blaOXA alongside blaCTX-M and qnrS were notable. Multiple plasmid types mobilized blaIMP-4 and blaOXA-1, and 121 isolates (28%) carried either a ColV-like (18%) or a pUTI89-like (10%) F virulence plasmid. Phylogenetic comparisons to human isolates provided evidence of interspecies transmission. Our study underscores the importance of bystander species in the transmission of antibiotic-resistant and pathogenic E. coli. © 2022 Wyrsch et al.