新疆北疆部分地区硬蜱伯氏疏螺旋体基因型研究

Isolation of Borrelia burgdorferi in ixodes from four counties, in North Xinjiang

目的调查和鉴定新疆北疆石河子市、沙湾县、伊宁县和察布查尔县媒介蜱，并确定其携带的莱姆病螺旋体的基因型。方法选择4县市6个牧区为调查点，采集羊源寄生硬蜱，结合形态学与16SrRNA进行蜱种鉴定；采用BSK．H培养基对莱姆病螺旋体分离培养，并用硝酸银染色和巢式PCR法进行病原检测，阳性产物测序结果比对，并与11种GenBank参考序列比对，确定莱姆病螺旋体的基因型。结果6个调查点共采集寄生硬蜱900多只，经形态学与16SrRNA鉴定分别为网兰扇头蜱、刻点血蜱、亚洲璃眼蜱和边缘革蜱；从中分别选取样本硬蜱共102只，分24管，分离培养后结合巢式PCR和硝酸银染色共获得16管阳性培养物。5S～23SrRNA基因间隔区测序比对分析表明，所有菌株为伯氏疏螺旋体与国际报道的B．burgdoferi Sensu Stricto（B31）基因型具有高度同源性，同源性为98．6％～99．5％；OspC基因型分析与上述结果一致。结论4县市分离获得伯氏疏螺旋体，基因型为B．burgdorferi Sensu Stricto，且存在生物多样性。从图兰扇头蜱中分离到伯氏疏螺旋体为我国首次报道。

Objective To identify ticks and determine the Borrelia （B.）burgdorferi genotype from four counties of northern Xinjiang. Methods Sheep ticks were collected from 6 surveillance sites in four counties including Shihezi, Shawan, Yining and Chabuchaer. All ticks were initially screened out based on morphological methods and 16S rRNA sequence analysis. B. burgdorferi was detected and cultivated with BSK-H medium. Combined with nested PCR, silver nitrate staining was employed to detect B. burgdorferi. Genotype of isolated B. burgdorferi was determined by Sequencing and phylogenic analysis based on 11 conference sequences. Results Hyalomma asiaticum asiaticum, Haemaphysalis punctata, Dermacentor marginatus and Rhipicephalus turanicus were identified from more than 900 ticks. Out of 24 tubes from 102 representative tick specimens, 16 tube were positive for B. burgdorfer. Sequencing of 5S-23S rRNA intergenic spacer showed 98.6%-99.5% identities to B. burgdo^feri Sensu Stricto （B31）. Results from the analysis of OspC genotype showed consistent with that of 5S-23S rRNA intergenic spacer. Conclusions 16 strains of B. burgdorferi Sensu Stricto were isolated in four counties, from northern Xinjiang. Additionally, B. burgdorferi Sensu Stricto was isolated from Rhipicephalus turanicus first time in China.