High-risk Escherichia coli global clones ST10 and ST155 in wild raptors admitted to a rehabilitation center

Abstract

The dissemination of extended-spectrum β-lactamase (ESBL)-producing Enterbacterales, once largely confined to healthcare settings, has become a growing One Health concern as these pathogens threaten diverse environments, including wildlife habitats. This study describes high-risk clones of ESBL-producing Enterobacterales in wildlife undergoing rehabilitation at a zoological park in Southeast Brazil. Among 49 wild mammals and birds sampled, two Escherichia coli strains, from a rusty-barred owl and a black vulture, tested positive for ESBL production and exhibited multidrug resistance profiles. Genomic characterization identified these strains as belonging to globally recognized clones of the sequence type (ST) ST10 and ST155, which are associated with widespread antimicrobial resistance (AMR) and severe infections in human and veterinary medicine. The strains harbored resistance genes for several antimicrobials and virulence factors typically found in extraintestinal pathogenic E. coli. ESBL-encoding genes were related to mobile genetic elements, with the bla_CTX-M-15 gene embedded in a multidrug resistance region flanked by Tn3 and IS26 elements and the bla_CTX-M-2 gene located on a complex class 1 integron. Accordingly, this study spotlights the potential role of wildlife rehabilitation centers as reservoirs for critical AMR, emphasizing the importance of monitoring such facilities for the presence of priority pathogens. Therefore, this study reinforces the necessity for microbiological surveillance in wildlife rehabilitation settings to prevent the spread of AMR into natural ecosystems and calls for the development of standardized guidelines for the reintroduction of animals to ensure that colonized wildlife do not contribute to the dissemination of resistant pathogens in the wild.

Keywords: Enterobacterales; CTX-M; Critical-priority bacteria; One health; Wildlife.