Occurrence of ESBL-Producing <i>Escherichia coli</i> ST131, Including the <i>H30</i> -Rx and C1-M27 Subclones, Among Urban Seagulls from the United Kingdom
Flavia Zendri, Iuliana E. Maciuca, Simon Moon, Philip H. Jones, Andy Wattret, Richard O. Jenkins, Andy Baxter, Dorina Timofte
Abstract
Antimicrobial resistance is a public health concern. Understanding any role that urban seagulls may have as a reservoir of resistant bacteria could be important for reducing transmission. This study investigated fecal Escherichia coli isolates from seagulls (herring gulls and lesser black-backed gulls) to determine the prevalence of extended-spectrum cephalosporin-resistant (ESC-R) and fluoroquinolone-resistant E. coli among gull species from two cities (Taunton and Birmingham) in the United Kingdom (UK). We characterized the genetic background and carriage of plasmid-mediated resistance genes in extended-spectrum β-lactamase (ESBL)-producing E. coli obtained from these birds. Sixty ESC-R E. coli isolates were obtained from 39 seagulls (39/78, 50%), of which 28 (28/60, 46.7%) were positive for plasmid-mediated CTX-M and/or AmpC β-lactamase resistance genes. Among these, blaCTX-M-15, blaCTX-M-14, and blaCMY-2 predominated. Three isolates belonging to the B2-ST131 clone were detected, of which two harbored blaCTX-M-15 (typed to C2/H30Rx) and one harbored blaCTX-M-27 and was typed to C1/H30-R (recently described as the C1-M27 sublineage). The plasmid-mediated quinolone resistance (PMQR) gene carriage prevalence (11.7%) consisted of aac(6′)-Ib-cr and qnrB genes. No carbapenem or colistin resistance genes were detected. Urban seagulls in the UK are colonized and can spread major antimicrobial-resistant E. coli isolates harboring ESBL and PMQR determinants, including clinically important strains such as the pandemic clone B2-ST131 and the C1-M27 subclade. This is the first report of ST131-C1-M27 subclade in wildlife in the UK and in seagulls worldwide.