福建省平潭岛春季恙虫病疫源地现场标本的芯片检测及防制措施

目的：利用基因芯片技术对平潭岛春季恙虫病疫区的恙虫病疑似病人、宿主、媒介标本进行检测,证实疫源地的存在,采取有针对性的防制措施控制流行.方法：现场采集恙虫病疑似病人外周静脉血和捕鼠采集体表恙螨.根据Ot 56kD外膜蛋白基因序列,设计群特异性引物及探针,制备寡核苷酸芯片.PCR技术分别扩增样本Ot DNA片段,与芯片上的探针杂交,用荧光扫描仪检测并分析信号;加强卫生宣传,做好个人防护,搞好环境卫生,做好灭鼠、灭螨等防制措施.结果：对疑似病人血块3份、野鼠脾脏40份、恙螨5份DNA进行基因芯片检测,其中病人血3份,野鼠脾脏4份,恙螨2份检出阳性;经过2年防制,该地区2004年无恙虫病病例报告.结论：基因芯片检测样本具有特异、灵敏、快速的特点,从基因水平证实平潭岛春季恙虫病存在,所采取的防制措施切实有效.

Field detection of samples of scrub typhus by DNA microassay and preventive strategies in spring at Pingtan Island in Fujiang province

Objective:To study field detection of samples from the suspected patients,rodents and mites by DNA microassay to confirm the existence of tsutsugamushi at Pingtan island in Fujiang province and make the preventive strategies in spring.Methods:The blood of the suspected patients,the spleens of the host rodents and the vector mites in the field were collected and the Ot NDA from these samples were extracted,respectively.The specific primers and probes were designed according to the conservative and specific DNA sequence of 56 kD protein of Orientia tsutsugamush.The probes were spotted on glass slides to form the microassays.The Cy3-labled Ot DNA fragment prepared by dissymmetical PCR was hybridized into the microassays.The microassays were scanned and analyzed with a scanner.The preventive strategies included propaganda of hygiene,personal protection,keeping environment clean and tide,eliminating rats and mites.Results:Identified by PCR,3 of 3 blood samples from the patients,4 of 40 spleens of rats and 2 of 5 mites had the 430 bp specific Ot DNA bands.After the preventive strategies were adopted for two years at this island,there was not any new report of tsutsugamushi case in 2004.Conclusion:The prepared DNA microassay can detect the DNA of Ot strains of scrub typhus with adequate specificity and sensitivity and the preventive strategies are correct and effective.