权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Survey for the cause of emerging dengue haemorrhagic fever in Southeast Asia

东南亚新发登革出血热病因调查

基本信息

批准号：
13576016
负责人：
MORITA Kouichi
金额：
$ 5.76万
依托单位：
Nagasaki University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

项目摘要

We conducted a study to find out the causes of dengue hemorrhagic fever (DHF) and its emergence in Southeast Asia, by : (a)isolating the dengue virus in many parts of the region ; (b)analyzing patient cells infected by the virus ; and (c)conducting a vector mosquito survey. We then analyzed the following three factors of the disease : 1)pathogen ; 2)host ; and 3)vector. In Thailand, a combination of dengue virus strains and the sensitivity of the mosquito vector was found to be associated with the spread of the virus. In the Philippines, a genotype shift of dengue virus type2 across the country was observed. In Vietnam, a new genotype of dengue type4 virus outbreak was witnessed. Also, Flowcytometry analysis in the Philippines and Vietnam demonstrated multipopulation of dengue virus infected cells in peripheral blood monocytes.In the past, two hypothesis on DHF were advocated, i.e., 1)virus virulence theory and 2)secondary infection theory. Our conclusion from these series of research is that both factors were concerned with the development, emergence and expansion of DHF in Southeast Asia. The evident physiological characteristic of DHF is its rapid plasma leakage from peripheral vessels. It should be clarified what viral protein(s) and kind of host cytokines are stimulating such rapid leak of plasma. It has also been noted that each population of Aedes aegypti caught from different localities demonstrated a unique susceptibility to dengue virus strains. The genotype shift of dengue 2 virus observed in the Philippines may have been promoted by a higher affinity of the newly introduced genotype of the virus. This indicates the possibility that rapid expansion of DHF during the 1960s may have been promoted by any virus mutation which enhanced virus and vector mosquito affinity. Further genetic analysis of dengue virus strains are necessary to clarify the mechanism of DHF emergence and rapid expansion in Southeast Asia.

我们进行了一项研究，通过以下方法找出登革出血热 (DHF) 的原因及其在东南亚的出现：(a) 在该地区的许多地方分离出登革热病毒； (b)分析被病毒感染的患者细胞； (c) 进行媒介蚊子调查。我们分析了该病的以下三个因素：1）病原体； 2）主机； 3）向量。在泰国，发现登革热病毒株和蚊子媒介的敏感性的组合与该病毒的传播有关。在菲律宾，观察到全国范围内2型登革热病毒的基因型发生转变。越南爆发了新基因型4型登革热病毒。此外，菲律宾和越南的流式细胞术分析表明，外周血单核细胞中存在登革热病毒感染细胞的复合群。过去，对于DHF提出了两种假说，即1）病毒毒力理论和2）继发感染理论。我们从这一系列研究中得出的结论是，这两个因素都与 DHF 在东南亚的发展、出现和扩张有关。 DHF 的明显生理特征是血浆从周围血管快速渗漏。应该澄清是什么病毒蛋白和宿主细胞因子刺激了如此快速的血浆泄漏。人们还注意到，从不同地点捕获的每个埃及伊蚊种群都表现出对登革热病毒株的独特易感性。在菲律宾观察到的登革热2病毒的基因型转变可能是由于新引入的病毒基因型的更高亲和力而促进的。这表明任何增强病毒和媒介蚊子亲和力的病毒突变可能促进了 20 世纪 60 年代 DHF 的快速扩张。有必要对登革热病毒株进行进一步的基因分析，以阐明 DHF 在东南亚出现和快速蔓延的机制。