Diagnosis, epidemiology and prevention of flavivirus infection including West Nile fever.

为了预防黄病毒感染的爆发，我们开发了诊断试验，检查了病毒的致病性，并检查了日本蚊子的媒介易感性。结果如下：1.诊断方法的建立：1）作为西尼罗病毒的基因诊断方法，建立了RT-PCR RFLP法、真实的时间PCR法和RT-LAMP法。建立了亚病毒颗粒IgG和IgM-ELISA，作为人血清学诊断试验。2.黄病毒致病性的研究西尼罗病毒纽约株的神经侵袭性毒力与囊膜蛋白的糖基化有关; 2）蜱传脑炎病毒的神经侵袭性毒力降低是由于囊膜蛋白的一个氨基酸改变导致病毒血症降低; 3）日本脑炎病毒1）2）RNAi技术是一种有效的抗乙型脑炎病毒药物。4.蚊虫研究1）发现4种日本本土蚊虫对西尼罗病毒易感。

In order to prevent the outbreaks of flavivirus infections, we developed the diagnostic tests, examined pathogenecity of the viruses and examined vector susceptibility of the Japanese mosquitoes. The results are summarized as follows.1.Development of diagnostic tests.1)As the genetic diagnostic tests of West Nile virus, RT-PCR RFLP method, a real time PCR method and RT-LAMP method were developed.2)For tick-borne encephalitis, IgG-and IgM-ELISA using subviral particles were developed as serological diagnostic tests for human.2.Studies on pathogenecity of flavivirus1)Neuroinvasive virulence of West Nile virus New York strain was found to be associated with glysosylation of envelope protein.2)Neuroinvasive virulence of tick-borne encephalitis virus was reduced due to one amino acid change of envelope protein which led to the reduced vircemia.3.Japanese encephalitis1)Japanese encephalitis virus from South-East Asian countries often invaded into Japan.2)RNAi was found to be effective as antiviral agent to Japanese encephalitis viris.4.Mosquito studies1)Japanese indigenous mosquitoes of 4 species were found to be susceptible to West Nile virus.