Abstract: Objective To investigate the serotype distribution,molecular typing and drug resistance of salmonella in foodborne pathogens in Pengzhou City from 2015 to 2022,and to provide scientific theoretical basis for rational drug use of salmonella infection and the outbreak and tracing of foodborne diseases in the future. Methods Food-borne disease isolates were collected from two food-borne disease surveillance sentinel hospitals in Pengzhou City from 2015 to 2022. Re-examination identification and serological typing of salmonella were carried out according to GB4789.4 and the instructions for diagnostic serums. Drug sensitivity tests and pluse-field gel electrophoresis（PFGE） were used to randomly select certain samples for typing. Results A total of 260 Salmonella isolates were collected from food-borne disease cases and 20 serotypes were identified. Among them,Salmonella typhimurium（71.15%） and Salmonella enteritidis（17.69%） were dominant. The 50 randomly selected Salmonella strains were divided into 44 PFGE band types,which showed diversity,and cluster band types appeared,there were 5 kinds of the same band types,each band type contained 2-3 strains,and the cluster similarity was 27.18%-100.00%. The 40 randomly selected Salmonella strains showed high resistance to ampicillin,streptomycin,tetracycline and nalidixic acid,100.00% sensitivity to azithromycin and amicacin,and >90.00% sensitivity to ertapenem,ceftazidime/avibactam and meropenem. 4 strains were sensitive to all antibiotics,7 strains were resistant to 1 or 2 antibiotics,and the remaining 29 strains had different degrees of multiple drug resistance,the multiple drug resistance rate was 72.50%,and the most resistant strains were resistant to 4 and 5 antibiotics,the highest was resistant to 9 antibiotics at the same time. Conclusions The main serotypes of salmonella in food-borne pathogens in Pengzhou from 2015 to 2022 are Salmonella typhimurium and Salmonella enteritidis.The PFGE band types of Salmonella are diverse,there is a risk of small epidemic,and the phenomenon of multiple drug resistance is serious.

Key words: Salmonella, Serotyping, Drug sensitivity test, Pluse-field gel electrophoresis