论文部分内容阅读
目的:了解2005年-2010年湖南省霍乱疫情分离到的O139群霍乱弧菌菌株的病原学特征,研究疫情分离株之间的克隆相关性。方法:采用K-B法进行药敏试验;聚合酶链反应(PCR)检测ctxAB毒力基因;脉冲场凝胶电泳对疫情分离代表株进行PFGE分型分析。结果:33株霍乱弧菌对强力霉素、复方新诺明的耐药率较高,分别为39.39%和75.76%,对环丙沙星、诺氟沙星以及丁胺卡那100%敏感;毒力基因的PCR结果显示为所有疫情分离的O139霍乱弧菌均为产毒株,即霍乱肠毒素基因ctxAB阳性;24株分离自2005年和2010年的7起疫情里的O139霍乱弧菌进行PFGE分型及聚类分析后,共分为3个PFGE带型,所有菌株的带型相似率在83%～100%之间。结论:湖南省2005年-2010年霍乱疫情以O139群为主,引起疫情的全部为产毒株,不同年份不同地区之间霍乱疫情的分离菌株之间存在着紧密相关的流行克隆群,对分离菌株进行耐药性监测和进一步的分子分型分析,有助于霍乱的主动监测和传染来源的追踪。
Objective: To understand the etiological characteristics of Vibrio cholerae O139 isolates isolated from the cholera epidemic in Hunan Province from 2005 to 2010 and to study the clonal correlation between the isolates of the epidemic isolates. Methods: K-B method was used to conduct drug susceptibility test. Polymerase chain reaction (PCR) was used to detect virulence genes of ctxAB. PFGE typing was performed on the representative isolates from epidemic situation by pulsed-field gel electrophoresis. Results: Vibrio cholerae showed strong resistance to doxycycline and cotrimoxazole, with 39.39% and 75.76% respectively, which was 100% sensitive to ciprofloxacin, norfloxacin and amikacin. PCR results of virulence genes showed that V. cholerae O139 isolated from all outbreaks were all toxigenic, that is, the cholera enterotoxin gene ctxAB was positive. 24 isolates of Vibrio cholerae O139 isolated from 7 outbreaks in 2005 and 2010 After PFGE typing and cluster analysis, there were three PFGE patterns. The similarities of all strains were between 83% and 100%. Conclusion: The epidemic of cholera was mainly O139 in Hunan province from 2005 to 2010. All of the outbreaks were caused by virus-producing strains. There were closely related epidemic clones among isolates of cholera epidemic in different regions in different years. Drug resistance monitoring and further molecular typing analysis of the strains will facilitate the active surveillance of cholera and the tracking of sources of infection.