CAREER: Dual Effects Of Intraspecific Competition On Pathogen Dynamics In A Songbird: From Endocrinology to Epidemiology

所有的生物体都必须不断抵抗有害病原体的感染。 然而，生物体抵抗病原体感染的能力不是恒定的，而是随着其物理和社会环境动态变化的。了解疾病易感性的关键环境介质至关重要，因为它们最终决定了大规模疾病爆发的可能性和程度。该项目的目标是调查物理和社会环境如何与鸣禽的生理相互作用，以影响疾病的易感性和人口水平的疾病爆发的程度。 该项目研究了与几乎所有生物体相关的环境因素-对有限食物资源的竞争-如何影响家雀（Carpodacus mexicanus）对其致弱性细菌病原体（鸡毒支原体，导致鸣禽可见的眼睛肿胀）的易感性。 细菌感染的过程将在不同的物理和社会环境下进行实验研究，实验结果将通过圈养传播研究，基于网络的模型和自由生活的家雀的实地研究扩大到人口水平的疾病结果。 这项工作的结果将大大提高我们对环境对宿主对病原体的易感性和疾病动态的作用的理解，并将允许更有针对性地管理人畜共患病和非人畜共患病的疾病爆发。 研究结果将由弗吉尼亚理工大学的研究生通过为初中和高中学生制作永久性的“疾病生态学”教育工具包来广泛传播。 因为鸣禽感染了M.鉴于鸡毒病菌在整个学年都在喂鸟器上随处可见，该项目的结果可以随时作为互动教育课程的基础。 工具包课程将在教师夏季研讨会上进行试点，并分发给弗吉尼亚理工大学的所有五个区域中心，供弗吉尼亚州的初中和高中教室广泛和长期使用。

All organisms must continually fight off infection with harmful pathogens. However, an organism's ability to resist pathogen infection is not constant, but varies dynamically with its physical and social environment. It is critical to understand key environmental mediators of disease susceptibility because they ultimately determine the likelihood and extent of large-scale disease outbreaks. The goal of this project is to investigate how the physical and social environment interacts with the physiology of songbirds to influence disease susceptibility and the extent of population-level disease outbreaks. The project examines how an environmental factor relevant to almost all organisms-- competition for limited food resources-- influences susceptibility of the house finch (Carpodacus mexicanus) to its debilitating bacterial pathogen (Mycoplasma gallisepticum, which causes visible eye swelling in songbirds). The course of bacterial infection will be examined experimentally under varying physical and social environments, and experimental results will be scaled up to population-level disease outcomes using captive transmission studies, network-based models, and field studies of free-living house finches. The results of this work will significantly improve our understanding of the role of the environment on host susceptibility to pathogens and disease dynamics, and will allow for more targeted management of zoonotic and non-zoonotic disease outbreaks. Results will be broadly disseminated by Virginia Tech graduate students through the creation of permanent "Disease ecology" education kits for middle and high-school students. Because songbirds infected with M. gallisepticum are readily visible at bird feeders throughout the school year, the project's results can readily serve as the basis for interactive educational curricula. Kit curricula will be piloted at teacher summer workshops and distributed to all five Virginia Tech regional centers for broad and long-term use in Virginia's middle and high school classrooms.