Hajer Kilani

Tunisia

Prevalence and antimicrobial resistance profiles of Enterobacterales isolated from companion animals and their owners in Tunisia

Hajer Kilani1,2,3, Sana Lengliz 3,5, Sana Ferjani1,6, Amira Jandoubi2,4, Ghassen Tayah2, Asma Ferjani1,6, Ilhem Boutiba-Ben Boubaker1,6, Lilia Messadi2, Mohamed Salah Abbassi1,3*
1Research Laboratory “Antimicrobial Resistance” (LR99ES09), Faculty of Medicine of Tunis, University of Tunis El Manar, 1006 Tunis, Tunisia,
2 Department of Microbiology, National School of Veterinary Medicine, 2020 Sidi Thabet, Tunisia,
3 Bacteriological Research Laboratory of the Institute of Veterinary Research of Tunisia, University of Tunis El Manar, Bab Saadoun, 1006 Tunis, 4 Veterinary Clinic, Bardo1, Tunis, Tunisia,
5 Laboratory of Materials, Molecules and Application, LR11ES22, Preparatory Institute for Scientific and Technical Studies, University of Carthage Tunis, Tunisia,
6 Department of Microbiology, Charles Nicolle Hospital, 1006 Tunis, Tunisia.

Abstract

Background

Antimicrobial resistance (AMR) represents a critical One Health challenge, threatening human, animal, and environmental health. Companion animals, including dogs and cats, can serve as reservoirs for antimicrobial-resistant Enterobacterales, posing potential risks for cross-species transmission to humans. However, the mechanisms and prevalence of AMR in companion animals remain poorly understood. This study investigates the prevalence and antimicrobial resistance profiles of Enterobacterales isolated from healthy and sick pets, as well as their corresponding owners, in Tunisia.

Methods

This study was conducted from From January to November 2024, samples were collected from 17 dogs, 22 cats, and 12 owners who participated voluntarily. For all 39 pets, samples were taken from rectal, oral, and nasal sites (three types of samples from each pets). Additional urine and abscess samples were obtained from 12 sick pets (8 cats and 4 dogs). A total of 141 samples, including 12 nasal swabs from owners, were cultured on Violet Red Bile Glucose (VRBG) agar following enrichment in brain heart infusion broth. Isolates were identified based on cultural, morphological, and biochemical characteristics. Antimicrobial susceptibility testing was performed using CLSI guidelines, and the Double-Disk Synergy Test screened for extended-spectrum beta-lactamase (ESBL) production.

Results

A total of 52 Enterobacterales isolates were obtained, predominantly Escherichia coli (n=41 pet, n=4 human). Other species detected just in pet included Providencia stuartii, Providencia rettgeri, Citrobacter freundii, Klebsiella oxytoca, Bordetella trematum, and Pantoea spp. High resistance rates were observed against amoxicillin (64.7%), streptomycin (60.7%), and trimethoprim/ sulfamethoxazole (45.1%), among others. Moderate resistance rates were noted for cefoxitin (23.5%) and cefotaxime (17.6%). Notably, 34.3% of isolates exhibited multidrug resistance, though no ESBL production was detected.

Conclusions

These findings underscore the urgent need for enhanced AMR surveillance and integrated One Health strategies to promote responsible antimicrobial use across human and veterinary medicine.