巢式-PCR检测蜱体中土拉弗氏菌的fopA基因及血清学调查  

DETECTION OF FRANCISELLA TULARENSIS IN TICKS BY USING NESTED-PCR AND SEROEPIDEMIOLOGICAL INVESTIGATION AMONG PEOPLE LIVING IN SOME AREAS OF SHAANXI PROVINCE IN CHINA

作　　者：李志清[1] 刘增加[2] 上官改珍[1] 何莹[1] 巨敏[1] 李旭光[1] 胡良煜[1] 徐燕[1] 

机构地区：[1] 解放军第323医院,西安710054 [2] 兰州军区疾病预防控制中心,兰州730020

出　　处：《寄生虫与医学昆虫学报》2014年第3期160-164,共5页Acta Parasitologica et Medica Entomologica Sinica

基　　金：全军医学科研“十一五”计划专项课题（082003）

摘　　要：为调查陕西省部分地区是否存在土拉弗氏菌病,采集子午岭山区的的蜱标本及人群血标本.蜱标本提取体内细菌DNA,采用巢式PCR法进行检测并对阳性标本进行基因分型;对人群血清采用免疫吸附实验进行血清学抗体检测;统计处理应用SPSS软件.结果在富县、陇县共采集3个蜱种1 116只蜱标本,其中达吉斯坦革蜱、日本血蜱、嗜群血蜱3个蜱种25只蜱标本检测到土拉弗氏菌的fopA基因,总阳性率为2.24％;不同蜱种阳性率存在差异,以日本血蜱的阳性率最高（15.39％）.从25份阳性标本中选取10份进行序列测序,获得核酸序列与土拉弗氏菌B亚种菌株序列AF247690.2 100％同源.对阳性标本进行SSTR9区域扩增,共有6种不同的拷贝数,其中以拷贝数9的占多数（40.00％）.利用MEGA （4.0）软件进行聚类分析显示主要分为两大群.检测当地居民血清标本725份,检测出土拉弗氏菌病血清IgG抗体阳性者37份,阳性率5.10％.本文首次证实陕西省土拉弗氏菌病的存在,对预防控制具有重要指导意义.To investigate Francisella tularensis infection in human and ticks collected in some areas of Shaanxi Province and to identify their genotypes of F. tularensis. Ticks were collected by dragging a cloth over the vegetation. After species identification, DNA of F. tularensis was isolated from ticks and detected by nested PCR targeting F. tularensis fopA gene. Positive samples were further amplified to discriminate the species and another two short-sequence tandem repeat regions （SSTR） were amplified to identify their genotypes. Human serum samples from local residents were examined for IgG antibody to F. tularensis by ELISA. A total of 1116 ticks including 3 tick species were captured, among which 25 samples were positive for the agent, the overall prevalence of F. tularensis was 2.24% %. All positive samples belonged to F. tularensis type B. The positive rates were significantly different among different tick species, with Haemaphvslis japanica having highest positive rate. 6 genotypes were identified in SSTR9 loci from 20 positive tick samples. Infection of F. tularensis in ticks and human and host indicate the presence of FranciseUa tularensisthat in Shaanxi Province and the necessary measures should be carried out to prevent and control of Tularemia.

关 键 词：蜱 土拉弗氏菌 基因型别 血清流行病学 

分 类 号：Q343[生物学—遗传学]