Analysis of contamination risk, drug resistance and virulence characteristics of cooked food pathogens in Tianjin
10.3760/cma.j.cn112309-20240202-00050
- VernacularTitle:天津市市售熟食致病菌分离鉴定、耐药及毒力特征分析
- Author:
Baolu ZHENG
1
;
Wen LI
;
Wei ZHANG
;
Aiping YU
;
Xiaohui LU
;
Guangwen LIU
;
Xiaoyan LI
;
Yunde LIU
Author Information
1. 天津医科大学医学检验学院，天津 300203
- Keywords:
Cooked food;
Whole genome sequencing;
gyrA;
parC;
Drug resistance;
Virulence
- From:
Chinese Journal of Microbiology and Immunology
2024;44(11):943-950
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To understand the contamination risk, drug resistance and virulence characteristics of cooked food pathogens in Tianjin.Methods:Pathogenic bacteria were isolated and identified in cooked food sold in Tianjin from 2019 to 2021, drug susceptibility test and whole genome sequencing were conducted for the isolates, and multilocus sequence typing, drug resistance gene, phenotype and virulence gene were analyzed for the data.Results:Ten pathogenic bacteria were isolated from 245 cooked food samples collected. The ST types of 7 Salmonella strains were ST40, ST198, ST14, ST13 and ST155. The two strains of Vibrio parahaemolyticus were ST647 and ST2622 respectively. One strain of Cronobacter sakazakii was ST8 type. All the 6 isolates were drug-resistant, and 3 of them were multidrug-resistant (MDR). A total of 63 drug-resistant genes were predicted in 10 isolates. Two Salmonella strains were ampicillin-chloramphenicol-streptomycin-sulfamethoxazole-tetracycline resistant (MDR-ACSSuT), and both Salmonella strains carried gyrA double mutations (S83F, D87N) and parC mutations (S80I). Vibrio parahaemolyticus mainly carries blaCARB and tet (35) genes, while Cronobacter sakazakii carries only one resistance gene blaCSA-1. A total of 163 virulence genes were predicted from 10 isolates. Conclusions:In this study, pathogenic bacteria are repeatedly detected in quail eggs, warning that other eggs besides chicken eggs should also pay special attention to the risk of contamination. The isolates in this study are all of the prevalent ST type with widespread drug resistance, and MDR-ACSSuT strains should be paid attention to. The key role of gyrA double mutation (S83F, D87N) and parC mutation (S80I) in the development of quinolone resistance should not be ignored. T3SS (typeⅢ secretory system) and T6SS (typeⅥ secretory system) are important virulence gene clusters of Salmonella and Vibrio parahemolyticus.
