北京昌平鼠间汉坦病毒感染时间动态变化的调查

目的 了解鼠类自然感染汉坦病毒（HV）时间动态变化。方法 选取北京昌平南口镇某部驻地，从2002年8月至2004年5月采用夹夜法捕获鼠形动物。针对汉坦病毒M基因部分片段设计SEOV和HTNV型特异性引物，应用RT-PCR法检测宿主肺组织中携带HV-RNA及其型别情况；应用ELISA法和IFAT接IFAT检测IgG抗体。利用SPSS软件分析宿主动物HV感染的时间动态特征。结果 共捕获啮齿动物296只，平均感染率11％。整个调查周期总体宿主种群密度波动不大，局部小生境（养殖场）种群波动明显。优势宿主褐家鼠平均种群密度与其感染率变化之间具相关性（r=0．594，P=0．023），养殖场褐家鼠密度与HV感染率之间相关性极显著（r=0．746。P=0．008）。褐家鼠性比和阳性率变化之间不具统计学意义相关性（r=0．541，P=0．086）。成幼比和阳性率变化之间则具显著相关性（r=0．697,P=0．046）。结论 北京昌平鼠间汉坦病毒感染长期持续存在，其感染率与种群密度随时问呈现动态变化，两者之间具有相关性，并因生境而异。优势宿主种群结构特征及其动态变化与HV感染也存在较为复杂的关系。

Investigation on the temporal dynamics of Hantavirus infection in rodents in Changping District of Beijing

Three niches in Changping district of Beijing were selected for a survey of the Hantavirus (HV) reservoirs, especially rodents, from Aug 2002 to May 2004, in which the temporal dynamic characteristics of the host animals captured in this area was investigated by means of RT-PCR using the SEOV and HTNV-type specific primers against parts of HV-M-gene fragment to detect the HV-RNA in the lung tissues of the host animals. ELISA and IFA were used to detect the IgG antibodies and the temporal dynamic characteristics was analyzed by EXCEL and SPSS software. A total of 296 rodents were captured with an average infection rate of 11%. Correlation existed between the average population density of the predominating host Rattus norvegicus and changes in infection rate (r=0.594, P=0.023), and the correlation between density of R norvegicus in breed sites and the HV infection rate was very significant (r=0.746, P=0.008). No significant correlation was found between the sex difference of R.norvegicus and the changes of positive rate of infection (r=0.541, P=0.086), but significant correlation existed between age difference of R.norvegicus and the changes of positive rate of infection (r=0.097, P=0.046). It is concluded that there appear to have long persistent HV infection in rodents from Changping county of Beijing and the prevalence of the rodent infection may be associated with fluctuation in R.norvegicus population. However there also exist a complex relationship among them. The temporal differences in acquisition of SEOV infection may expand the understanding of the risk factors for acquiring HFRS.