Pathogenic Escherichia coli in Dogs Reveals the Predominance of ST372 and the Human-Associated ST73 Extra-Intestinal Lineages

Abstract

Escherichia coli is a ubiquitous commensal and pathogen that has also been recognized as a multi-sectoral indicator of antimicrobial resistance (AMR). Given that latter focus, such as on resistances to extended-spectrum cephalosporins (ESC) and carbapenems, the reported population structure of E. coli is generally biased toward resistant isolates, with sequence type (ST)131 being widely reported in humans, and ST410 and ST648 being reported in animals. In this study, we characterized 618 non-duplicate E. coli isolates collected throughout France independently of their resistance phenotype. The B2 phylogroup was over-represented (79.6%) and positively associated with the presence of numerous virulence factors (VFs), including those defining the extraintestinal pathogenic E. coli isolates (presence of ≥2 VFs: papA, sfaS, focG, afaD, iutA, and kpsMTII) and those more specifically related to uropathogenic E. coli (cnf1, hlyD). The major STs associated with clinical isolates from dogs were by far the dog-associated ST372 (20.7%) and ST73 (20.1%), a lineage that had commonly been considered until now as human-associated. Resistance to ESC was found in 33 isolates (5.3%), along with one carbapenemase-producing isolate, and was mostly restricted to non-B2 isolates. In conclusion, the presence of virulent E. coli lineages may be the issue, rather than the presence of ESC-resistant isolates, and the risk of transmission of such virulent isolates to humans needs to be further studied.

Characteristics of Extended-Spectrum β-Lactamase–Producing Escherichia coli From Dogs and Cats Admitted to a Veterinary Teaching Hospital in Taipei, Taiwan From 2014 to 2017

“…A French study also reached a similar conclusion, identifying ST372 as the major pathogenic E. coli ST in dogs (42). Similar findings in two distinct geographic areas may indicate a dog-specific distribution of pathogenic E. coli clones instead of the effect of regional factors (42). In contrast to LeCuyer's and Valat's reports, ST372 was observed only once in our study.…”

“…They therefore concluded that each host species may have a particular ST that comprises most of the E. coli uropathogens. A French study also reached a similar conclusion, identifying ST372 as the major pathogenic E. coli ST in dogs (42). Similar findings in two distinct geographic areas may indicate a dog-specific distribution of pathogenic E. coli clones instead of the effect of regional factors (42).…”

Genome evolution and the emergence of pathogenicity in avian Escherichia coli

“…The prevalence of APEC-associated variants, used in the RF model, was investigated in isolates sampled from other host niches. Specifically, we analysed the E. coli reference collection (ECOR) 42 , 175 human ExPEC strains 28 , 14 disease-associated strains from dogs 51 and 521 strains from healthy cattle 52 . The APEC-associated genetic variants also occurred in humans and other animals implying that host species does not constitute a complete gene-pool barrier between the niches.…”

Multidrug-Resistant CTX-M and CMY-2 Producing Escherichia coli Isolated from Healthy Household Dogs from the Great Metropolitan Area, Costa Rica

“…45 Among the MLST genotypes reported in this study, some of them have been isolated in both humans and animals; in particular, ST372, ST410, and ST224 have been reported previously in humans and pets. 48,49 This shows that these, and probably many other E. coli genotypes carrying antimicrobial resistance genes, can be shared between animals and humans.…”