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

Virginia Polytechnic Institute And State University, Blacksburg VA

Investigators

Abstract

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.