Occurrence of ampicillin-resistant Enterococcus faecium carrying esp gene in pet animals: An upcoming threat for pet lovers.

Objectives: This study was carried out to investigate oral colonisation by Enterococcus faecalis and Enterococcus faecium in pet dogs and cats, with special reference to antibiotic resistance.

Methods: Oral swabs were collected from 63 pet dogs and 57 pet cats with no known history of hospitalisation. All samples were enriched in Kenner Fecal (KF) broth before being cultured on KF agar to isolate enterococci. E. faecalis and E. faecium were identified by biochemical and molecular techniques. Antimicrobial resistance was determined by the disk diffusion method, and ampicillin-resistant strains were further examined by PCR to detect the esp gene.

Results: Oral prevalence rates of E. faecalis among pet dogs and cats were 3.2% and 5.3%, respectively, whilst those for E. faecium were 22.2% and 15.8%, respectively. None of the isolated enterococci were resistant to vancomycin. However, ampicillin-resistant E. faecium (AREfm) was detected in the examined dogs and cats at rates of 14.3% and 5.3%, respectively. Moreover, among the isolated enterococci, six isolates showed multidrug resistance (all AREfm). Whilst the esp gene was detected in only two of nine canine AREfm isolates (multidrug-resistant strains), none of feline AREfm isolates harboured esp.

Conclusions: The occurrence of AREfm and the esp gene among oral isolates from pet dogs and cats represents a great public health hazard for pet owners and highlights possible zoonotic transmission of such a nosocomial pathogen outside healthcare facilities.