Extended-Spectrum β-Lactamase-/AmpC-Producing Escherichia coli and Associated Risk Factors in Shelter Dogs: A Baseline Study in North Macedonia

Abstract

Antimicrobial resistance (AMR) is a significant public health concern in companion animals, yet systematic surveillance in North Macedonia is lacking. This study investigated the prevalence of resistance in Escherichia coli isolated from 112 fecal samples from dogs in six shelters in North Macedonia and evaluated the associated risk factors, providing the first baseline dataset for this population. High resistance was observed for sulfamethoxazole (68.75%), ampicillin (52.68%), and ciprofloxacin (41.07%). Multidrug resistance was present in 50% of the isolates, with 17 (15.17%) confirmed as ESBL producers. Additionally, 18 isolates (16.1%) were identified as AmpC producers, 16 of which carried the blaCMY-2 gene. Notably, 72.2% of ESBL/AmpC isolates were resistant to ertapenem despite the absence of carbapenemase genes, a finding that warrants further investigation. Risk factors such as shared housing, longer shelter stays, and frequent empirical antimicrobial use were identified as probable contributors to the carriage of ESBL-/AmpC-producing E. coli. None of the shelters had antimicrobial stewardship protocols or routine diagnostic testing, revealing critical gaps in infection control and antimicrobial practices. These findings underscore the urgent need for antimicrobial stewardship and surveillance in North Macedonia’s companion animal populations within the One Health framework.