A fatal brain disease affecting deer and elk could pose an increasing risk of spreading to humans and livestock, warns a landmark report released today by infectious disease experts at the University of Minnesota.
The comprehensive analysis, which brought together 67 experts from across North America and Europe, outlines critical gaps in surveillance and preparedness for a potential “spillover” of chronic wasting disease (CWD) from deer to other species. The report marks the first major effort to prepare for what experts characterize as a low-probability but potentially devastating scenario.
“Since we began working on this report in 2023, concerns about a CWD prion spillover from cervids to other animal species and humans have only continued to grow in importance, and we’re simply not prepared should a species jump occur,” said Michael T. Osterholm, PhD, MPH, director of the Center for Infectious Disease Research and Policy (CIDRAP) at the University of Minnesota.
The disease, first identified in Colorado in 1967, has now spread to 35 U.S. states and multiple countries including Canada, Norway, and South Korea. CWD is caused by infectious proteins called prions that trigger devastating brain damage, leading to inevitable death in affected animals. These prions can spread through bodily fluids and persist in the environment for years.
‘The Day After’ Scenario
The report represents a shift in how experts are approaching CWD, moving beyond current management to consider worst-case scenarios. “This is the first time in my experience that a multidisciplinary and truly One Health approach has been taken towards this disease, and the first time we’ve begun to consider ‘the day after’—what wildlife managers, agricultural experts, and human health professionals would be up against if spillover occurred,” said Russ Mason, PhD, a wildlife conservation expert who co-chairs CIDRAP’s wildlife working group.
While no human cases have been documented, the report emphasizes that the risk isn’t static. As CWD becomes more prevalent in wild deer populations, the chances of the disease adapting to infect new species increase. The emergence of new prion strains could make cross-species transmission more likely.
Brian Appleby, MD, who directs the National Prion Disease Pathology Surveillance Center and co-chairs the project’s public health working group, noted this evolving risk: “Although basic science research suggests that there is a low likelihood of the disease transmitting to humans, this may change over time due to variations in chronic wasting disease strains as it continues to spread, as well as the possibility of it infecting other animals in which transmission to humans may be more likely.”
Critical Gaps in Preparedness
The report identifies several vulnerabilities in current monitoring and response capabilities. Most state wildlife agencies lack consistent disease surveillance programs, and available resources would be “grossly insufficient” if CWD were to jump species. There is currently no vaccine or treatment for the disease.
Beyond the immediate health concerns, a spillover event could have far-reaching consequences for food safety, agriculture, and international trade. The report warns that the economic implications could be severe, particularly if CWD were to spread to livestock.
Nine-Point Action Plan
To address these gaps, the report outlines nine key recommendations, including:
- Establishing dedicated, multi-year funding streams for CWD research and management
- Strengthening partnerships between wildlife managers, agricultural experts, and healthcare providers
- Improving surveillance through advanced prion strain typing in wild animals
- Enhancing physician education to improve detection and reporting of potential human cases
- Developing comprehensive plans for contaminated carcass disposal
The study, titled “Chronic Wasting Disease Spillover Preparedness and Response: Charting an Uncertain Future,” was supported by the Minnesota Department of Natural Resources and builds upon recent work by the National Academies of Sciences, Engineering, and Medicine.
The findings underscore the urgent need for coordinated action across multiple sectors to prepare for a potential crisis that, while not inevitable, could have devastating consequences if it occurs. As CWD continues to spread across North America and beyond, the window for implementing these preparedness measures may be narrowing.