Abstract：Objective To analyze the drug resistance status and molecular typing features of part of Salmonellae isolated from market-sold food in Guangzhou City, and to provide experimental data for prevention and control of diseases caused by Salmonella. Methods Salmonella strains isolated from food samples were serotyped, antibiotic susceptibility test was carried out, pulsed-field gel electrophoresis (PFGE) was used to conduct genotyping, and BioNumerics software was used for analyzing the homology. Results From 2016 to 2018, a total of 16 strains of Salmonella were isolated from food, of which 6 strains serotype Derby were dominant. Antibiotic resistance test showed that the Salmonella strains isolated were highly resistant to penicillins, of which drug resistance rate of the Salmonella strains to ampicillin was the highest (56.3%), followed by cefotetan (25.0%). PFGE analysis revealed that 16 strains of Salmonella were divided into 10 PFGE genotypes, and the overall similarity ranged between 41.5% and 100.0%. 2 genotypes of the food-borne strains had high similarity with 2 of more than 800 strains isolated from patients and obtained during the same period. The highest similarity between food-borne and human-derived strains was 93.3%. Conclusion Salmonella Derby was dominant serotype of the Salmonellae detected from food in Guangzhou. Antimicrobial resistance and genotypes of the Salmonellae were diversified. It is found that there is a high similarity between some food-borne strains and human-derived strains, suggesting that some genotypes of Salmonellae have high risk of causing disease.
2022, Vol. 29 
