Delineating EEEV Over-Wintering and Early Season Amplification Mechanisms

描述（由申请方提供）：东部马脑脊髓炎病毒（EEEV）是美国最具致病性的虫媒病毒。人类的脊髓灰质炎病例虽然是零星的，难以预测，但非常严重，超过35%的有症状病例是致命的，大多数幸存者患有长期的神经系统并发症。佛罗里达是美国EEEV活动最多的地区，占所有报告的人类病例的25%，最近的证据表明，佛罗里达是EEEV传播到其他州的水库。EEEV没有有效的治疗方法或FDA批准的疫苗。因此，预防感染依赖于监测以发现病毒传播，然后采取措施试图防止病毒传播给人类。这些措施的有效性取决于对EEEV传输动态的理解，而这种理解仍然有限。特别是，研究人员一直无法确定EEEV如何以及在何处越冬，以及它如何从冬季周期过渡到鸟类宿主的地方病扩增。获得一个了解的机制，在佛罗里达的EEEV越冬和赛季初放大将使我们能够预测何时何地这些过程可能会发生。这将导致有可能制定在季节早期阻断传播的战略，这可能会减少或防止EEEV在夏季晚些时候爆发，因为蚊子密度较大，干预费用相应较高。此外，如果佛罗里达成为全国其他地区EEEV的储存地，那么早期季节干预措施可以通过防止EEEV从佛罗里达传播到其他州来保护全国大部分地区。为了实现这一总体目标，提出了以下具体目标：1。验证蛇是EEEV重要越冬宿主的假设。2.描述佛罗里达EEEV冬季和早春地方性传播的宿主和媒介。3.为了检验假设，涉水鸟类栖息地代表EEEV扩增的重要焦点。4.制定佛罗里达早期EEEV传播的风险图。这样的风险地图将是非常宝贵的，在预测EEEV越冬和早期季节放大的焦点，允许有效的早期季节干预策略的发展。

DESCRIPTION (provided by applicant): Eastern equine encephalomyelitis virus (EEEV) is the most pathogenic arbovirus endemic to the USA. Human cases of EEE, although sporadic and difficult to predict, are very serious, with over 35% of symptomatic cases being fatal and most survivors suffering long term neurological complications. Florida has the most EEEV activity in the US, with 25% of all reported human cases, and recent evidence suggests that Florida is a reservoir from which EEEV is disseminated to other states. There is no effective treatment or FDA approved vaccine for EEEV. Thus, prevention of infection relies upon surveillance to detect viral transmission, followed by measures to try to prevent the spread of the virus to humans. The effectiveness of these measures rests upon an understanding of the dynamics of EEEV transmission, and this understanding remains limited. In particular, researchers have been unable to determine how and where EEEV over-winters, and how it transitions from its winter cycle into enzootic amplification in avian hosts. Gaining an understanding of the mechanisms of over-wintering and early-season amplification of EEEV in Florida will allow us to predict when and where these processes may be occurring. This will lead to the possibility of developing strategies to interrupt transmission early in the season, which may lessen or prevent outbreaks of EEEV later in the summer, when mosquito densities are greater and the costs for intervention correspondingly higher. Furthermore, if Florida serves as the reservoir for EEEV for the rest of the country, early season interventions may protect much of the country by preventing dissemination of EEEV from Florida to other states. To accomplish this overall goal, the following Specific Aims are proposed: 1. To test the hypothesis that snakes are important over-wintering hosts for EEEV. 2. To delineate the hosts and vectors of winter and early spring enzootic transmission of EEEV in Florida. 3. To test the hypothesis that wading bird rookeries represent important foci for EEEV amplification. 4. To develop a risk map for early season EEEV transmission in Florida. Such a risk map will be invaluable in predicting foci of EEEV over-wintering and early season amplification, permitting the development of effective early season intervention strategies.