RAPID: Linking population dynamics and behavior to understand how wildfire modifies the prevalence of zoonotic disease

An estimated 60% of pathogens that affect humans, including the novel coronarvirus, also infect wild animals. This project examines Sin Nombre virus (SNV), a causative agent of hantavirus pulmonary syndrome in humans, in wild mouse populations. In particular, this work evaluates how wildfires, which are increasing in frequency and severity, affect disease dynamics. Knowledge of wildfire effects on disease in animal populations is incomplete because pre-fire data rarely exist to make informed post-fire comparisons, and because wildfires can simultaneously affect animal behavior, abundance, and movement. This project will help identify mechanisms whereby wildfire modifies disease in animals, thereby providing benefits to society by improving the ability to predict how future wildfires will affect disease in wildlife and humans. The project will also provide ways to mitigate human disease risk by identifying which intervention strategies are likely to be most successful for reducing post-fire disease in wildlife populations. Through outreach the project will educate the public about how wildfire affects infectious disease. In addition, the project will provide significant opportunities for training graduate students underrepresented in STEM fields. This project evaluates how wildfire affects the prevalence of SNV via the effects of wildfire on deer mouse (Peromyscus maniculatus) demography and behavior. Intensive immediate post-fire demographic, behavioral, and environmental data will be combined with existing long-term, pre-fire data. The project occurs on Santa Cruz Island, CA and capitalizes on a recent wildfire in June 2020. The objective of the project is to evaluate three hypotheses that link disturbance and the prevalence of zoonotic disease. 1) Sex-based differences in dispersal yield changes in prevalence by altering the composition of post-fire populations. 2) Changes in vegetative structure in post-fire habitats drive local changes in animal abundance that modify contact rates and disease prevalence. 3) Homogeneous resources and risk in post-fire habitats serve to synchronize the timing of animal activity, increasing contact rates and prevalence. 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.