Virginia CWD Risk Assessment and Surveillance Plan

Principal Investigator: Krysten Schuler

Department of Population Medicine and Diagnostic Sciences
Sponsor: Virginia Department of Wildlife Resources
Grant Number: EP3278012
Title: Virginia CWD Risk Assessment and Surveillance Plan
Project Amount: $20,296
Project Period: December 2020 to November 2021

DESCRIPTION (provided by applicant): 

Chronic Wasting Disease (CWD) is a progressive, fatal, degenerative neurological disease of captive and free ranging deer, elk, and moose. First identified in research deer in Colorado in the 1960’s, it has now spread to wild and captive deer and elk in 26 states, Canada, and Scandinavian countries. In locations where it has become established, the disease has been detrimental to population health. In Wyoming where the disease is endemic, prevalence rates have reached over 50% in some areas. CWD-infected deer don’t live as long as uninfected deer, they may be more vulnerable to predators, and heavily infected deer populations can see population declines over time.

States’ experience has shown CWD is exceptionally difficult to manage in captive and wildlife populations. Deer or elk infected with CWD may shed prions, but exhibit no symptoms for a year or more. Prions are also extremely resilient in the environment; they may remain infectious for at least 16 years. CWD prions are almost impossible to remove because of their persistence in the environment; they bind to soil and are taken up into plant tissues. There is no vaccine or treatment for this disease, and it is always fatal. Early detection provides the best opportunity for intervention by wildlife managers. Therefore, proactive prevention efforts and rapid response to disease outbreaks are critical for disease management.

CWD monitoring in Virginia has been ongoing and has detected CWD in Virginia in 2009. Detections in West Virginia, Maryland, and Pennsylvania increase the risk to Virginia. Virginia Department of Wildlife Resources (VDWR) recognizes that prevention efforts, monitoring, and early detection are critical for disease management. To increase the likelihood of early detection in new areas of the state, sampling and testing should be focus on geographic areas of highest disease introduction risk, along with sex and age distributions most affected. Risk of disease introduction and spread may be increased with movement of infected deer, live or dead, and their parts and fluids.

The goals of the proposed project are 1) to assess and quantify risk factors for the introduction of CWD in Virginia, and 2) design a scientifically-based statewide CWD surveillance plan with early detection as a principle aim. This surveillance plan will include a weighted sampling approach that integrates deer population and demographic information, while including elements of potential CWD risk in proportion to their occurrence in individual sampling units.