四川石渠县牦牛源蜱感染斑点热群立克次体分子流行病学调查  

Molecular detection of spotted fever group rickettsiae-infected ticks collected from yaks in Shiqu County of Sichuan Province, China

作　　者：刘城成 唐天才 塔英 林宝山 袁东波[3] 郭莉[3] 侯巍[3] 莫茜[3] 阳爱国[3] 郝力力[1] 李锐[4] LIU Cheng-cheng;TANG Tian-cai;TA Ying;LIN Bao-shan;YUAN Dong-bo;GUO Li;HOU Wei;MO Xi;YANG Ai-guo;HAO Li-li;LI Rui(College of Life Science&Technology,Southwest Minzu University,Chengdu 610041,China;Center for Animal Disease Control and Prevention in Abazhou,Maerkang 624000,China;Center for Animal Disease Control and Prevention in Sichuan Province,Chengdu 610041,China;Institute of Quality and Standard for Agro-products,Zhejiang Academy of Agricultural Sciences,Hangzhou 310021,China)

机构地区：[1]西南民族大学/生命科学与技术学院,成都610041 [2]阿坝州动物疫病预防控制中心,马尔康62400 [3]四川省动物疫病预防控制中心,成都610041 [4]浙江省农业科学院农产品质量标准研究所,杭州310021

出　　处：《中国人兽共患病学报》2020年第1期50-55,共6页Chinese Journal of Zoonoses

基　　金：西南民族大学研究生创新项目（No.CX2019SZ127)~~

摘　　要：目的了解四川省石渠县牦牛体表寄生蜱的种类及其斑点热群立克次体的感染情况。方法采集牦牛体表的蜱,经形态学初步鉴定后,提取蜱总DNA,PCR扩增蜱16S rRNA基因及斑点热群立克次体ompA、ompB基因,并对扩得阳性产物进行测序和构建进化树分析,从而确定蜱及其携带斑点热群立克次体的种类。结果在石渠县4个乡共采集到蜱818只,其中西藏革蜱占78.97%(646/818)、青海血蜱占21.03%(172/818)。在818只蜱中有408只扩得斑点热群立克次体ompA、ompB基因,总阳性率为49.8%。经比对分析,ompA基因总共得到4条序列(uncultured Rickettsia sp.shiqu1、R.raoultii.shiqu2、R.raoultii.shiqu3和R.raoultii.shiqu4),ompB基因也得到4条序列(uncultured Rickettsia sp.shiqu1、R.raoultii.shiqu2、R.raoultii.shiqu3和R.raoultii.shiqu4)。经遗传进化分析显示ompA基因的uncultured Rickettsia sp.shiqu1与我国青海未定种的Uncultured Rickettsia sp.(MG228270)亲缘关系最近;ompB基因的uncultured Rickettsia sp.shiqu1与韩国未定种的Rickettsia sp.(KC888953)和Candidatus Rickettsia longicornii(MG906675)亲缘关系最近;ompA和ompB基因的R.raoultii.shiqu2-4与对人有致病性的劳氏立克次体(R.raoultii)的亲缘关系最近。结论首次在牦牛体表寄生的西藏革蜱中检出劳氏立克次体。石渠县存在西藏革蜱和青海血蜱,蜱传劳氏立克次体感染率较高并且具有感染人的风险。In order to investigate tick species and the percentage of spotted fever group rickettsiae positive in ticks collected from yaks in Shiqu County, Sichuan Province, the ticks were first classified by morphological identification. The total DNA of ticks was extracted and partial sequences of 16 S rRNA of ticks, ompA and ompB gene of SFG rickettsia were amplified by PCR,respectively. The positive products were sequenced and compared through the NCBI database and phylogenetic trees were constructed based on 16 S rRNA, ompA and ompB for determination of ticks species and spotted fever group rickettsia, respectively. A total of 818 ticks were collected from 4 villages in Shiqu County and only Dermacentor everestianus(78.97%, 646/818) and Haemphysalis qinghaiensis(21.03%, 172/818) were found. The total infection rate of SFG rickettsia in ticks was 49.8%. Four sequences of ompA(Uncultured Rickettsia sp.shiqu1, R.raoultii.shiqu2, R.raoultii.shiqu3 and R.raoultii.shiqu4) and four sequences of ompB(Uncultured Rickettsia sp.shiqu1, R.raoultii.shiqu2, R.raoultii.shiqu3 and R.raoultii.shiqu4) were obtained. Phylogenetic analysis showed that: for ompA, uncultured Rickettsia sp.shiqu1 had the closest relationship with the uncultured Rickettsia sp.(MG228270)isolated from Qinghai;for ompB, uncultured Rickettsia sp.shiqu1 had the closest relationship with the uncultured Rickettsia sp.(KC888953)and Candidatus Rickettsia longicornii(MG906675)isolated from Korea. R.raoultii.shiqu2-4 for ompA and ompB gene had the closest relationship with the human pathogenic R.raoultii. In this study, R.raoultii was first detected in D.everestianus from yaks. At present, only D. everestianus and H. qinghaiensis were found in Shiqu with high infection rate of R. raoultii and there exists a high risk of human infection.

关 键 词：斑点热群立克次体 牦牛 蜱 分子流行病学 石渠县 

分 类 号：R384.4[医药卫生—医学寄生虫学] S855.99[医药卫生—基础医学]