Genotyping and antimicrobial susceptibility characteristics of human and foodborne Salmonella in Nan'an District of Chongqing from 2019 to 2022
10.3969/j.issn.1673-4130.2024.12.007
- VernacularTitle:2019-2022年重庆市南岸区人源和食源性沙门菌分型及药敏特征分析
- Author:
Caiyun LI
1
;
Jing YIN
;
Lingyu GONG
;
Siyu ZHOU
;
Yi LUO
;
Li FENG
;
Hua ZONG
Author Information
1. 重庆市南岸区疾病预防控制中心微生物检验科,重庆 401336
- Keywords:
Salmonella;
serotype;
drug resistance;
multilocus sequence typing;
whole genome se-quencing
- From:
International Journal of Laboratory Medicine
2024;45(12):1442-1447,1452
- CountryChina
- Language:Chinese
-
Abstract:
Objective To understand the serotype,molecular typing and drug sensitivity characteristics of Salmonella isolated from food and stool samples of diarrhea patients in Nan'an District of Chongqing.Methods A total of 71 Salmonella strains isolated from food and stool samples of diarrhea patients in Nan'an District of Chongqing from 2019 to 2022 were serotyped,and the drug resistance of the strains was determined by the micro-broth dilution method.Multilocus sequence typing(MLST)was performed on 2 Salmonella Ken-tucky strains,and whole genome sequencing was performed on 8 Salmonella typhimurium strains and 2 Sal-monella typhimurium variants.Results The 71 strains of Salmonella included 13 serotypes.A total of 48 Sal-monella strains were isolated from stool samples of diarrhea patients,with Salmonella typhimurium(56.25％,27/48)and Salmonella enteritidis(18.75％,9/48)as the main serotypes.A total of 23 Salmonella strains were isolated in food samples,with Salmonella Rissen(26.09％,6/23)as the predominant.The total drug re-sistance rate of 71 strains of Salmonella was 97.18％.The highest drug resistance rate was ampicillin(69.01％),followed by tetracycline(64.79％),compound sulfamethoxazole(43.66％)and chloramphenicol(43.66％).The multidrug resistant strains accounted for 61.97％(44/71),including 60.42％(29/48)of stool samples of diarrhea patients and 65.22％(15/23)of food samples.The two Salmonella Kentucky strains iso-lated from food and diarrhea patients were resistant to 7 and 8 types,respectively,with the largest number of drug resistant types in the corresponding samples.The MLST types of both Salmonella Kentucky strains was ST198 type.The MLST types of 8 Salmonella typhimurium strains selected for sequencing were ST19,and the MLST types of 2 Salmonella typhimurium monophasic variants were ST34.The genetic relationship of Salmo-nella typhimurium with the same ST type was different.Conclusion The serotypes of Salmonella isolated from Nan'an District of Chongqing are diverse and the drug resistance is serious.The detection of ST198 Sal-monella Kentucky is more accurate by using whole genome sequencing than MLST.The surveillance of Sal-monella serotypes,molecular typing and drug resistance should be strengthened.
