Studies on the pathogenesis and transmission of dengue hemorrhargic fever

在泰国东北部登革热流行地区之一的那空Phanom，对“登革出血热的发病机制和传播”进行了实地研究，得出以下结论：(1)如果提供ELISA阅读器和一些关键试剂（登革抗原和酶标记抗体），IgM-ELISA是实验室确认登革病毒感染的合适方法。然而，RT-PCR不适用于实验室条件尚未建立的偏远地区的常规诊断。病毒分离是进一步详细分析研究的必要条件。(2)从患者血液标本中分离出1型、2型和3型登革热病毒株，确认那空县仍是登革热高流行区之一。(3)在检测的几种细胞因子中，ifn - γ水平在登革热患者中比FUO患者更频繁地升高，即使在急性期也是如此。(4)旱季临床诊断为登革热的患者可能感染了其他病原体。(5)埃及伊蚊雌成虫在旱季和雨季均有捕获，以黑色亚种居多，呈腹背虎纹。不幸的是，在这些蚊子中没有检测到登革热病毒基因组，这使得在未来的研究中对病毒易感性和这些蚊子的藏身之处留下了答案。(6)在旱季对经研究确定的埃及伊蚊藏身地选择性施放奥利赛特网。由于这种选择性的应用减少了登革热媒介蚊子的数量，因此可以在有限的资源下有效地控制登革热

Field studies on the "Pathogenesis and transmission of dengue hemorrhgic fever" in Nakhon Phanom, Northeast Thailand, one of the dengue endemic areas, gave following results :(1) IgM-ELISA is an approprioate method for laboratory confirmation of dengue virus infection, if an ELISA reader and some key reagents (dengue antigen and enzyme-labelled antibodies) were provided. While, RT-PCR is not suitable for routine diagnosis in remote areas where laboratory conditions have not been established. Virus isolation is essential for further detailed analytical studies.(2) Dengue virus type 1,2, and 3 strains were isolated from patient's blood specimens, confirming that Nakhon Phanom is stil one of the dengue-hyperendemic areas.(3) Among several cyotkines examined, IFN-gamma level was elevated more frequently in dengue patients, even in the acute phase, than FUO patients.(4) Patients clinically diagnosed as dengue during dry season are probably infected with other agents.(5) Many female adult Aedes aegypti were captured both in dry and rainy seasons, and most of them were black subspecies with abdominal dorsal tergal pattern 1. Unfortuantely, dengue virus genome was not detected in any of these mosquitoes, leaving the answer for virus susceptibility and hiding places of these mosquiatoes in future studies.(6) Olyset net was selectively applied to those hiding places of Aedes aegypti, which were identified by the studies in dry season. Since such a selective application reduced the number of dengue vector mosquitoes, the method can be utilized for the effective control of dengue with limited amount of resources