Ecology of Encephalitis Viruses in the USA

东部马脑脊髓炎病毒（EEEV）是一种严重的人类感染性疾病，被列为高度传染性疾病。 结果选择代理。在上一个资助期间进行的研究中，我们证明了 美国中东南部的 EEEV 生态与北大西洋各州的生态有根本不同。我们 研究表明，EEEV 的嗜鸟载体对鸟类宿主表现出暂时变化的偏好， 研究结果表明，这些载体优先针对雏鸟和当年的雏鸟（YOY）。我们 开发了一个模型，表明以雏鸟为食和 YOY 是推动 EEEV 的传输。我们还在年初和物种中发现了 EEE 感染的证据 主要以爬行动物和两栖动物为食。该项目的总体目标将是建立在这些基础上 研究结果进一步了解 EEEV、其载体和脊椎动物宿主的相互作用如何导致 病毒的维持、禽类地方性动物病的发展以及病毒从地方性动物疫源地的逃逸 感染人类和马。该项目的具体目标是： 1. 为了检验 EEEV 媒介蚊子优先以 YOY 为食的假设，使用微卫星 基于方法来识别个体水平的禽类血粉。 2. 估计Cx的觅食范围。 erraticus，东南部主要的 EEEV 媒介。 3. 测量两栖类和爬行类的EEEV暴露和储存能力。 4. 确定Cx的向量能力。错误，Cx。啄木鸟和乌尔。 EEEV 的 sapphirina。 5. 检验某些越冬蚊子参与维持病毒的假设 冬季。 总之，这些努力将使我们能够确定该病毒最重要的载体， 越冬机制、非禽类宿主以及病毒从其传播的动态 地方性动物疫病集中于周边地区。当我们的模型参数化时，这些数据将允许我们预测 导致禽类流行病发生和传播的最重要因素 传染给其他物种，包括人类。

Eastern equine encephalomyelitis virus (EEEV) is a serious infection of humans, and is listed as a high- consequence select agent. In studies carried out during the previous funding period, we demonstrated that EEEV ecology in the mid- Southeastern USA differs fundamentally from that in the North Atlantic states. We have shown that ornithophilic vectors for EEEV exhibit temporally shifting preferences for avian hosts, a finding that suggests that these vectors preferentially target nestlings and young-of-the-year (YOY). We have developed a model that suggests that feeding on nestlings and YOY is an important factor driving the transmission of EEEV. We have also found evidence for EEE infection very early in the year and in species that feed primarily upon reptiles and amphibians. The overall goal of this project will be to build upon these findings to further understand how the interaction of EEEV, its vectors and vertebrate hosts results in maintenance of the virus, the development of avian enzootics and the escape of the virus from enzootic foci to infect humans and horses. The specific aims of the project are: 1. To test the hypothesis that EEEV vector mosquitoes feed preferentially upon YOY, using a microsatellite- based method to identify avian blood meals to the individual level. 2. To estimate the foraging range of Cx. erraticus, the major EEEV vector in the Southeast. 3. To measure EEEV exposure and reservoir competence of amphibians and reptiles. 4. To determine the vector competence of Cx. erraticus, Cx. peccator and Ur. sapphirina for EEEV. 5. To test the hypothesis that certain over-wintering mosquitoes are involved in maintaining the virus during the winter months. Together, these efforts will allow us to identify the most significant vectors for the virus, the potential mechanism for over-wintering, non-avian reservoirs, and the dynamics of spread of the virus from its enzootic focus to surrounding areas. When parameterized in our model, these data will allow us to predict the most important factors responsible for the development of an avian epizootic and for the spread of that epizootic to other species, including humans.