Zhang J Z, Fan M Y, Bi D Z
Department of Rickettsiology, Chinese Academy of Preventive Medicine, Beijing, People's Republic of China.
Acta Virol. 1995 Dec;39(5-6):263-7.
The polymerase chain reaction (PCR) technique for amplification of genomic fragments of spotted fever group (SFG) rickettsiae directly from field samples of ticks, tick ova, tick larvae, tick faeces and organs of wild mice was employed for the first time in P.R. of China. Ticks and rodents were collected in Beijing and Heilongjiang, Hainan and Hebei Provinces. The PCR primers were designed from the DNA sequence encoding the 190 K protein of R. rickettsii for a 532 bp long product. Seven of ten tick samples, three of four tick ovum samples, one of two tick larva samples, four of seven tick faeces samples (the samples represented pools of several individuals), and two of twenty-seven wild mouse organs were found PCR-positive. In comparison with PCR assay, the haemolymph test gave similar but not so clear-cut results. PCR assay is recommended as a rapid, sensitive and convenient tool for the detection of SFG rickettsiae in endemic foci. The fact that tick faeces were found to certain extent PCR-positive for the presence of SFG rickettsiae is apparently the first report on this subject and contributes to the knowledge of the transmission of these micro-organisms in the nature.
中国首次采用聚合酶链反应（PCR）技术，直接从蜱、蜱卵、蜱幼虫、蜱粪便及野生小鼠器官的野外样本中扩增斑点热群（SFG）立克次体的基因组片段。蜱和啮齿动物采自北京、黑龙江、海南和河北省。PCR引物是根据编码立氏立克次体190K蛋白的DNA序列设计的，扩增产物长度为532bp。在10个蜱样本中有7个、4个蜱卵样本中有3个、2个蜱幼虫样本中有1个、7个蜱粪便样本（这些样本代表多个个体的混合样本）中有4个以及27个野生小鼠器官中有2个经PCR检测呈阳性。与PCR检测相比，血淋巴检测结果相似但不那么明确。推荐将PCR检测作为在疫源地检测SFG立克次体的一种快速、灵敏且便捷的工具。在一定程度上发现蜱粪便经PCR检测呈SFG立克次体阳性这一事实显然是关于该主题的首次报道，有助于了解这些微生物在自然界中的传播情况。
