# Pandemic human-associated extended-spectrum β-lactamase-producing Escherichia coli lineages of ST38, ST131 and ST141 identified in Viennese dogs

## TL;DR

Viennese dogs carry ESBL-producing E. coli with high multi-drug resistance and virulence, including human-associated lineages.

## Contribution

Identifies pandemic human-associated E. coli lineages (ST38, ST131, ST141) in dogs in Vienna with high multi-drug resistance and virulence.

## Key findings

- 14.8% of dogs carried ESBL-producing E. coli.
- Half of isolates belonged to human-associated lineages including ST38, ST131, and ST141.
- 53.8% of isolates were multi-drug resistant and all carried virulence genes.

## Abstract

To assess the prevalence of ESBL Enterobacteriaceae among dogs attending a veterinary clinic in Vienna, characterize the isolates in terms of antimicrobial resistance, virulence and phylogenetic relationships.

Faecal samples of 88 dogs were streaked on selective plates, species were identified by MALDI-ToF MS, tested for resistance by a combination disk test and VITEK 2®, whole genome-sequenced, bioinformatically genotyped, phylogenetically analysed and screened for resistance and virulence genes.

ESBL Escherichia coli carriage rate was 14.8% (95% CI: [8.1–23.9]). No carbapenem resistance was found, but 53.8% of the isolates were classified genotypically as multi-drug resistant. Phylogenetic analyses revealed that half of the isolates belonged to animal and environment-associated phylogroups, while another half was human-associated, and included high-risk international clones of ST38, ST131 and ST141, which clustered primarily with human isolates. All isolates harboured various virulence-associated genes, including four isolates that encoded exotoxins, of which two were from the pandemic ST131 and emerging ST141 lineages.

Dogs in Vienna carry ESBL E. coli with high rates of multi-drug resistance and virulence, and a highly diverse population structure that includes pandemic human-associated lineages.