Thermal Community Ecology of Disease

在下个世纪，世界上许多地区将经历气候和温度变化的加速。在其他影响中，热环境的变化可能会影响传染病的爆发，从而增加或降低植物、动物和人类感染的风险。温度通常通过依赖温度的增长率和病媒(例如蚊子)、寄主物种(例如人类、农作物或野生动物)以及寄生虫或病原体本身(例如细菌或真菌)的其他生物学特征与传染病的模式联系在一起。然而，疾病往往是由宿主、病媒和寄生虫组成的三部曲之外的其他物种塑造的。例如，捕食者通常会降低猎物种群中的疾病严重性，相互竞争的物种经常会干扰彼此寄生虫的传播。此外，不同的热环境往往比其他物种更有利于某些物种--例如，捕食者胜过猎物，或者一个竞争者胜过另一个竞争者。因此，气温的变化可能会以释放或抑制传染病的方式重组生态群落。这项研究的结果将通过模型和实验证明，温度变化如何通过这些生态途径影响传染病的结果。该项目还将通过为本科生和研究生提供机会，支持让当地社区参与并扩大对科学的参与的外联活动。这个项目的目标是了解温度如何影响包括宿主、寄生虫、资源、竞争对手和捕食者在内的生态群落中的传染病动态。实验的中心是一个由浮游动物宿主、真菌寄生虫和捕鱼者组成的模型系统。这个研究系统中以前的实验表明，温度升高会增加极简主义社区(仅限于寄主和寄生虫)疾病爆发的严重程度，但来自湖泊的现场数据表明，在更复杂和现实的社区，温度升高可能会降低疾病严重程度。将获得所有涉及的物种的相关性状的热性能曲线，并用于对一般力学模型进行参数化。然后，将通过在温度梯度上进行的独立的多代中观实验来测试参数化模式。模型和中观实验都将被设计成反映日益复杂的群落，包括：i)仅寄主、资源和寄生虫，ii)添加竞争对手，iii)添加捕食者，以及iv)添加竞争对手和捕食者。模型和实验的整合将为一个新的领域奠定坚实的基础，该领域致力于研究温度对生态社区疾病动态的影响：疾病的热社区生态学。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Over the next century, many parts of the world will experience accelerated rates of change in climate and temperature. Among other impacts, altered thermal environments are likely to affect outbreaks of infectious disease, resulting in elevated or diminished risk of infection for plants, animals, and people. Temperature is typically linked to patterns of infectious disease through temperature-dependent growth rates and other biological traits of disease vectors (e.g., mosquitos), host species (e.g., humans, crops, or wildlife), and the parasites or pathogens themselves (e.g., bacteria or fungi). However, disease is often shaped by other species beyond this trifecta of hosts, vectors, and parasites. For example, predators often reduce disease severity in populations of their prey, and species that compete against each other frequently interfere with the transmission of each other’s parasites. Moreover, different thermal environments often favor some species over others – for example, predators over prey or one competitor over another. Thus, changes in temperature could re-assemble ecological communities in ways that unleash or inhibit infectious disease. Results of this research will demonstrate, with both models and experiments, how variation in temperature shapes infectious disease outcomes through these ecological pathways. This project will also support outreach events that engage the local community and broaden participation in science by providing opportunities for undergraduate and graduate students. The goal of this project is to understand the ways in which temperature shapes infectious disease dynamics in ecological communities that include hosts, parasites, resources, competitors, and predators. The experiments center on a model system of zooplankton hosts, fungal parasites, and fish predators. Previous experiments in this study system have shown that warmer temperature increases the severity of disease outbreaks in minimalistic communities (just hosts and parasites), but field data from lakes suggests that warmer temperature might decrease disease severity in more complex and realistic communities. Thermal performance curves of relevant traits will be obtained for all species involved and used to parameterize general mechanistic models. Parameterized models will then be tested with independent multi-generational mesocosm experiments conducted across thermal gradients. Both models and mesocosm experiments will be designed to reflect increasingly complex communities, including: i) only hosts, resources, and parasites, ii) adding a competitor, iii) adding a predator, and iv) adding both competitor and predator. The integration of models and experiments will establish robust foundations for a new field that grapples with effects of temperature on disease dynamics in ecological communities: the thermal community ecology of disease.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.