Predicting the Risk of Pathogen Introductions from Disease Surveillance Data

• Activity Number: 322 - Analyses in Ecology, Epidemiology, and Environmental Policy
• Type: Contributed
• Date/Time: Wednesday, August 11, 2021 : 3:30 PM to 5:20 PM
• Sponsor: Section on Statistics and the Environment
• Author(s): Nelson Walker* and Trevor Hefley and Daniel Walsh and Ian McGahan and Daniel Storm and Daniel Skinner
• Companies: Kansas State University, Department of Statistics and Kansas State University, Department of Statistics and U.S. Geological Survey - National Wildlife Health Center and University of Wisconsin, Department of Statistics and Wisconsin Department of Natural Resources and Illinois Department of Natural Resources
• Keywords: Bayesian hierarchical models; Mixture models; Indicator variable selection; Ecological diffusion; Bayesian imputation; Chronic wasting disease

Abstract

In the course of an infectious disease outbreak, researchers often must estimate or infer the source of the causative pathogen, the risk factors associated with the spread and growth of the pathogen, and risk factors that may be associated with new outbreaks. Because the exact time and location of introduction for the pathogen is usually unobserved, these questions must be addressed using incomplete or indirect data, such as spatio-temporal disease surveillance data. We introduce a Bayesian hierarchical mixture model for spatio-temporal, binary disease surveillance data that accounts for the dynamic process of the pathogen diffusing and multiplying through a population from multiple sources. Our framework provides approximate posterior estimates for the number, locations, and times of introduction of the pathogen in a population, as well as posterior inference on parameters associated with pathogen growth and diffusion. We also obtain posterior inference on the generative spatial process that produced the pathogen introductions. We demonstrate this framework using disease surveillance data for chronic wasting disease in white-tailed deer from Wisconsin and Illinois in the USA.