Prevalence and Antimicrobial Susceptibility of Salmonella in Retail Meat Collected from Different Markets in Sichuan, China.

Salmonella is one of the most significant zoonotic and foodborne pathogens, and it is the leading cause of bacterial diarrhea. In this study, 156 retail meat samples were collected from three supermarkets and one local wet market in Sichuan, China, including 96 chicken samples and 60 pork samples. The prevalence of Salmonella in these samples was analyzed, and 91 samples (58.33%) tested positive, with 60 (62.5%) positive chicken samples and 31 (51.67%) positive pork samples. From these positive samples, 190 Salmonella isolates were confirmed by double PCR. Subsequent serotyping identified nine serovars, with the predominant ones being S. London (58.94%), S. Typhimurium (12.58%), and S. Enteritidis (10.60%). Antibiotic susceptibility test revealed that 168 isolates (88.42%) were resistant to at least one antibiotic, and 150 isolates (78.95%) were resistant to three or more antibiotics. The highest resistance rates were observed for ampicillin (83.16%), followed by tetracycline (76.31%) and trimethoprim/sulfamethoxazole (67.37%). In the disinfectant susceptibility test, Salmonella isolates exhibited higher resistance rates to benzalkonium bromide (100%) and benzalkonium chloride (97.37%), while showing a lower resistance rate to potassium monopersulfate triple salt (33.6%). These findings highlight the high prevalence of Salmonella and its significant resistance to antibiotics and disinfectants, indicating that effective measures must be implemented to ensure the microbiological safety of retail meat.