2015—2017年新疆动物源鼠伤寒沙门菌耐药性分析

Drug resistance of Salmonella Typhimurium isolated from animals in Xinjiang, 2015-2017

关键词:  不同动物源  鼠伤寒沙门菌  耐药性  耐药基因

Key words:  different animal origin  Salmonella typhimurium  drug resistance  drug resistance genes

摘要:

为完善新疆动物源鼠伤寒沙门菌耐药的相关数据，为多重耐药病源菌的防控提供依据，本研究检测了2015—2017年新疆不同动物源鼠伤寒沙门菌的流行情况、耐药特性及耐药基因携带率。对经选择性培养基和特异性PCR鉴定的不同动物源鼠伤寒沙门菌，通过琼脂稀释法进行环丙沙星等12种抗菌药物的最小抑菌浓度测定，同时采用PCR方法测定耐药基因在鼠伤寒沙门菌中的携带情况。结果表明:从不同动物中共分离获得162株鼠伤寒沙门菌，分离率由高到低依次为宠物(犬和猫)、猪、羊、牛和鸡；药敏试验显示，不同动物源鼠伤寒沙门菌对环丙沙星、氨苄西林、四环素和氟苯尼考的耐药率>80.0%，未检出对阿米卡星和磷霉素耐药的耐药菌株。从不同动物源分离的162株鼠伤寒沙门菌中有159株菌为多重耐药菌株，占98.1%；不同动物源鼠伤寒沙门菌多重耐药均以CIP-AMP-TET-FFC-SMZ 5耐谱型为主。经耐药基因分析，不同动物源鼠伤寒沙门菌耐药基因检出率为6.8%~97.4%，未检出bla_SHV、qnrD、rmtB和mcr-1基因。综上，鼠伤寒沙门菌在新疆不同动物中流行率高，耐药现象严重，多重耐药菌株较多且耐药基因携带率高，部分不同动物源菌株间具有相同的耐药表型和耐药基因型。应加强畜牧业抗菌药物使用的管理制度，进而控制鼠伤寒沙门菌耐药性的发展趋势。

Abstract:

In order to investigate the drug resistance of Salmonella typhimurium isolates of animal origin and provide the support data for the prevention of multidrug resistant pathogens, the prevalence of S. typhimurium isolates, antimicrobial resistance profiles and relevant resistance genes were characterized in Xinjiang, from 2015 to 2017. Selective medium and specific PCR were used to isolate S. typhimurium strains. Minimum inhibitory concentrations(MICs)of ciprofloxacin and other 12 antimicrobial agents were determined by Agar dilution method according to CLSI recommendation. Several PCR sets were designated to detect different resistance genes in these isolates. A total of 162 S. typhimurium strains were obtained from different animals, and the isolation rate from high to low was pet(dog and cat), pig, sheep, cattle and chicken. The MIC tests showed that resistance rates of ciprofloxacin, ampicillin, tetracycline and florfenicol were more than 80. 0%, while no resistant to amikacin and fosfomycin were observed. Among the 162 strains of S. typhimurium isolates, 159(98. 1%)strains exhibited multi-resistance. The most common resistance profile was CIP-AMP-TET-FFC-SMZ for S. typhimurium strains from detected animals. The detection rate of resistance genes of S. typhimurium was between 6. 8% and 97. 4%, bla_SHV, qnrD, rmtB and mcr-1 genes were not detected. In conclusion, the prevalence of S. typhimurium in different animals in Xinjiang is very high, and the phenomenon of drug resistance is serious. There are many multi-drug resistant strains and higher carrying rate of drug resistance gene. Some stains of different animal origin have the same resistance phenotype and drug resistance genotype. The management system of antibiotic use in animal husbandry should be strengthened to control the development trend of drug resistance of S. typhimurium.