Prevalence and molecular characteristics of carbapenem-resistant Escherichia coli isolated from dogs in South Korea.

Abstract

Importance: Carbapenem-resistant Enterobacteriaceae are emerging as a global public health risk. Therefore, assessing the prevalence of carbapenem-resistant Escherichia coli (CRE) in both humans and animals is important.

Objective: We aimed to ascertain the occurrence and characteristics of CRE isolated from companion animals, dogs and cats.

Methods: E. coli strains were tested for antimicrobial susceptibility using the broth microdilution technique. Antimicrobial resistance genes were detected by polymerase chain reaction and sequencing analysis. The molecular characteristics of CRE were determined using multi-locus sequence typing, replicon typing, and pulsed-field gel electrophoresis (PFGE).

Results: In total, 13 CRE isolates (0.13%) were identified from dogs possessing bla_NDM-5 along with β-lactamase genes, mostly bla_CMY-2 (92.2%) and bla_TEM-1 (53.8%). The commonly observed mutations were S83L and D87N in gyrA, S80I in parC, and S458A in parE. CRE carried non-beta-lactam resistance genes, with the majority being tet(B) (100%), sul (84.6%), and aac(3)-II (53.8%). Nine different PFGE patterns (P1-P9), IncX3-type plasmids (69.2%), and ST410 (84.6%) were predominantly detected.

Conclusions and relevance: This investigation provides significant insight into the prevalence and molecular characteristics of bla_NDM-5-carrying E. coli in dogs. The co-existence of bla_NDM-5 and other antimicrobial resistance genes in E. coli potentially poses severe health hazards to humans.