1株人源mcr-1阳性多重耐药沙门菌的特征分析

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中图分类号：S182 文献标识码：A 文章编号：0488-5368（2025）06-0013-09

Abstract：Salmonella，a zoonotic pathogen， poses a serious threat to human health and the development of animal husbandry. In China，multidrug resistance in Salmonell from both human and animal sources is a severe concern，with potential forcross-transmission.In2019，127 human fecal samples were collected from five hospitals in Henan Province. Salmonella was isolated using SS agar plates supplemented with 2μg/mL colistin and identified via Gram staining，biochemical tests，and PCR amplification targeting the 16S rRNA and invA genes. The presence of the colistin resistance gene mcr-1 was assessed，and antimicrobial susceptibility testing using the microbroth dilution method was conducted to evaluate the strains resistance to 15 commonly used antibiotics. Whole -genome sequencing was performed to analyze the strain’s genetic characteristics.A total of six Salmonella strains were identified （positivity rate： 4.7% ），among which one was mcr -1 -positive. The strain’s MIC for colistin was 8μg/mL . MLST identified the strain as ST34. It harbored multiple resistance genes，including blaTEM-116，bla CTX -M-14，bla OXA -1，oqxAB， tet（A） ， floR，catB3，catA1，sul1，sul2，sul3， （20 ant（3′′） ，aph ，and dfrA12. The isolate was resistant to colistin，ampicillin，amoxicillin，ceftiofur， ceftazidime，gentamicin，spectinomycin，tetracycline，florfenicol，chloramphenicol，sulfisoxazole，sulfamethoxydiazine，enrofloxacin，and ciprofloxacin.The mcr-1-bearing plasmids were transferable and showed high similarity to previouslyreported IncHl2 plasmids，both in Chinaand abroad.Strengthening infection control measures and rational antibiotic use are esential to delaythe emergence of drug -resistant Salmonella strains.

Key words：Salmonella; Colistin； mcr -1； bla CTX -M-14；Multidrug Resistance

mcr－1阳性多重耐药沙门菌是一种人畜共患病病原。（剩余12845字）