Phylogenomic Analysis of CTX-M-15-Positive Escherichia coli from Companion Animal Reveals Intercontinental Dissemination of ST90 Within a One Health Framework.

The global dissemination of extended-spectrum-β-lactamase (ESBL)-producing Escherichia coli has been considered a critical issue within a One Health framework. The aim of this study was to perform a genomic investigation of an ESBL-producing E. coli strain belonging to the globally spread sequence type/clonal complex ST90/CC23, isolated from gastrointestinal tract of a dog, in Brazil. Besides CTX-M-15 ESBL, this E. coli isolate carried mutations conferring resistance to human and veterinary fluoroquinolones (GyrA [Ser83Leu, Asp87Asn], ParC [Ser80Ile] and ParE [Ser458Ala]), and resistance determinants to disinfectants and pesticides. Noteworthy, phylogenomic analysis revealed that this multidrug E. coli strain clustered with ST90 lineages isolated from human, dog, and livestock in Brazil. The phylogenetic tree also revealed that this E. coli strain shares a common ancestor with isolates from the United States, Russia, Germany, and China, highlighting the potential global spreading of this clone. In summary, we report genomic data of CTX-M-15-positive E.coli ST90 colonizing a pet. Colonization of companion animals by critical resistant pathogens highlights the need for close monitoring to better understand the epidemiology and genetic factors contributing for successful adaptation of global clones at the human-animal interface.