When Prions Cross Into New Territory — Wildlife Officials Respond

On a quiet winter field where mule deer once roamed with casual grace, a more unseen and troubling pattern is making its presence known. In Utah’s wild landscapes — from forested hillsides to high desert plateaus — wildlife managers have long watched for a fatal illness that can rip through cervid populations with silent persistence. Now that watch has sharpened: chronic wasting disease (CWD) has been detected in deer across more parts of the state, prompting concern and heightened monitoring from state wildlife officials.

CWD is a neurodegenerative prion disease that attacks the brain and nervous system of deer, elk and moose, ultimately proving fatal to affected animals. While it has been present in Utah since the early 2000s — first identified in a hunter‑harvested mule deer near Vernal — recent test results show the disease may be spreading into new geographic areas, including near Scofield in Carbon County and additional regions of Uintah County, according to the Utah Division of Wildlife Resources (DWR).

From July 1, 2025, through February 23 of this year, DWR biologists collected over 2,100 samples from deer across the state as part of routine surveillance and mandatory hunter check stations, and 83 of those samples tested positive for CWD. The positive detections included animals harvested by hunters as well as those found in newly sampled regions where the disease had not previously been confirmed.

For decades, wildlife managers have grappled with chronic wasting disease’s slow but steady advance across North America, where it now occurs in dozens of states and provinces. The disease spreads between animals through direct contact, or indirectly via contaminated saliva, urine, feces, or soil laden with prions — misfolded proteins that can persist in the environment for years.

In its early stages, infected deer can appear healthy and continue to behave normally, which can make detecting and containing the disease particularly challenging. Over time, however, affected animals may lose weight, exhibit droopy ears, excessive drooling or listless behavior before succumbing to the illness. As a prion disease much like scrapie in sheep or “mad cow disease” in cattle, CWD currently has no known cure or effective treatment once an animal is infected.

Despite its expansion into newly confirmed areas of Utah, the risk of transmission to humans is considered extremely low. Federal health agencies and state wildlife officials do not recommend consuming meat from animals known to be infected with CWD, and advise hunters to have harvested deer tested before consuming the meat when hunting in areas where CWD has been detected.

In response to the evolving distribution of CWD, the Utah Division of Wildlife Resources continues its surveillance program and has implemented mandatory testing in some hunting units while adjusting outreach to hunters about bringing harvested animals to check stations for sampling. This effort helps produce a clearer picture of where the disease is present and supports adaptive management strategies to monitor and, where possible, slow its spread.

While finding the disease in additional parts of the state does not necessarily mean an immediate crisis, wildlife managers emphasize the importance of early detection and consistent monitoring. Understanding where CWD occurs helps inform hunting regulations, population management plans, and public messaging, particularly in areas newly affected. Ongoing research into the disease’s ecology and long‑term impact on deer populations underscores the importance of vigilance in wildlife health monitoring.

In practical terms, Utah wildlife officials have confirmed chronic wasting disease in more deer populations, including in areas near Scofield and parts of Uintah County where it had not previously been documented. The disease remains fatal to infected deer and can spread through contact or environmental contamination, and the Division of Wildlife Resources continues to expand its testing and outreach to track and respond to this spread.

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Sources KSL News TownLift Utah Division of Wildlife Resources press announcements Wildlife.utah.gov chronic wasting disease overview News Minimalist summarizing recent spread reports