2018年北京市O1群霍乱弧菌表型及分子分型特征分析

目的了解2018年北京市O1群霍乱弧菌表型及分子分型特征。方法2018年收集北京市霍乱患者和外环境分离的29株霍乱弧菌，应用常规鉴定方法进行血清分型，荧光定量PCR检测霍乱弧菌ctxAB基因，应用96孔微量肉汤稀释法进行药物敏感试验（11类21种试验药物），应用NotⅠ及ShifⅠ酶切进行脉冲场凝胶电泳（PFGE）分子分型。结果29株O1群霍乱弧菌中小川型非产毒株、稻叶型非产毒株和小川型产毒株构成比分别为62.07%（18/29）、24.14%（7/29）和13.79%（4/29）；29株菌头孢唑林耐药率最高82.76%，美罗培南敏感率100.00%；28株菌耐药；有9种耐药型别，最多耐13种药；有13种耐药类别，最多耐7类药；29株菌株PFGE分子分型为16个型别（BJ1801 ~ 1816）。结论北京市O1群霍乱弧菌以非产毒株为主，多重耐药严重；PFGE分子分型结果提示应注意食品安全问题，特别要加强水产品的监测。

Characteristics of phenotype and molecular type of Vibrio cholerae O1 in Beijing, 2018

ObjectiveTo understand the characteristics of the phenotype and molecular type of Vibrio cholerae O1 in Beijing in 2018.MethodsThe strains of V. cholerae were isolated from cholera cases and external environments. Serotyping was performed for the strains with routine identification methods, and V. cholerae toxin gene were detected by using real-time PCR. The sensitivities of the strains to 21 kinds of antibiotics was conducted with micro-broth dilution method. Pulsed field gel electrophoresis (PFGE) with Xba Ⅰ and Not Ⅰ restriction enzymes was performed for the molecular typing of V. cholerae O1 strains.ResultsIn 29 V. cholerae O1 strains isolated, the proportions of non-toxin producing Ogawa strains, non-toxin producing Inaba strains and toxin producing Ogawa strains were 62.07% (18/29), 24.14% (7/29) and 13.79% (4/29) respectively. The resistance rate of the strains to cefazolin was highest (82.76%), all the strains were sensitivity to meropenem (100.00%). Twenty eight strains were drug resistant with 9 drug resistance types, the highest was resistant to 13 antibiotics; there were 13 resistance categories to 11 classes of antibiotics, the highest was resistant to 7 classes of antibiotics. Results from PFGE indicated that the 29 V. cholerae strains were classified into 16 molecular types.ConclusionV. cholerae O1 was mainly non-toxic in Beijing, and multi drug resistance of V. cholerae O1was severe. The results of PFGE molecular typing suggested that the attention should be paid to food safety, especially to strengthen the monitoring of aquatic products.