Serotype Occurrence, Virulence Profiles, Antimicrobial Resistance and Molecular Characterization of Salmonella Isolated from Hospitalized Patients with Gastroenteritis in Great Tunisia between 2010 and 2020

Non-typhoid is one of the major causes of food-borne infections worldwide. The aim of the current study is to determine the serotype occurrence, virulence factors and antimicrobial resistance patterns of isolated from hospitalized patients. The identification of strains was performed according to REMIC, 2018. The susceptibility of isolates was assessed against 20 antimicrobials using the disk diffusion method. Some virulence and antimicrobial resistance genes were identified using PCR. Among the 61 isolated strains, seven serotypes were identified and all were positive for the virulence genes , and . Critical resistance rates (>40%) were detected for tetracycline, nalidixic acid, amoxicillin and fluoroquinolones. However, resistances to ertapenem, ceftazidim, aztreonam and colistin were null. In addition, 33% of the isolated strains were multidrug-resistant (MDR). Moreover, 80% and 60% of . Kentucky isolates were identified as fluoroquinolone-resistant and MDR strains, respectively. The gene was amplified in 63.2% of fluoroquinolone-resistant strains. The gene was identified in 20% (4/20) of the trimethoprim-sulfamethoxazole resistant strains and the integrase Class 2 gene was amplified in only 8.2% (5/61) of the isolates. Our findings highlight the emergence of MDR isolates. A rationalization of antimicrobial use is urgently recommended in both human and veterinary medicine.