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Authorities Confirm First Known Case of Zombie Deer Disease in Yellowstone

Unfortunately, chronic wasting disease, commonly called zombie deer disease, has made its way to Yellowstone.

By Cassidy Ward
A zombie clown appears in Zombieland (2009).

There are enough zombie movies streaming right now on Peacock – Night of the Living Dead, Day of the Dead, Day of the Dead 2, ZombielandZombie Night, Zombie Hunter, Train to Busan, the list quite literally goes on and on – to create your own multi-day zombie movie marathon. You should do that, by the way, and make sure to include Zoombies, the only zombie flick with the guts to wonder what might happen if the zombie contagion impacted animals instead of us.

If you thought human zombies were scary, wait until you see the undead lions, tigers, and bears of Zoombies. If movies aren't your cup of tea, though, you can unfortunately find zombie deer in the real world as one of the latest additions to Yellowstone National Park.

Yellowstone Officials Find Patient Zero for Zombie Deer Disease in the Park

The National Park Service recently confirmed the first known case of chronic wasting disease (CWD), commonly called “zombie deer disease” in an adult mule deer found near Yellowstone Lake. The dead buck had previously been captured as part of a population dynamics study conducted by the Wyoming Game and Fish Department (WGFD) and fitted with a collar. The collar signaled that the animal had died in mid-October 2023 and WGFD worked with Yellowstone officials to locate the carcass and collect tissue samples for study.

RELATED: Zombie Fungus Forces Flies to Get Freaky with Dead Mates


After multiple diagnostic tests, officials confirmed the presence of the disease which commonly impacts deer, elk, moose, reindeer, and sika deer across parts of North America, Norway, and South Korea. Symptoms are caused by a malformed protein (prion), the same thing that causes mad cow disease in animals and Creutzfeldt-Jakob Disease, Kuru, and a number of other diseases. The malformed proteins collect in the brain where they cause other proteins to fold incorrectly.

The resulting behavioral changes manifest as excessive drooling, head lowering, weight loss, listlessness, and ultimately death. From the date of infection, it can take a year or more for symptoms to present and death to occur. Unfortunately, the NPS notes there is no effective strategy for getting rid of CWD once it has rooted itself in a population. Efforts are focused on managing the disease within populations through increased monitoring and investigation of carcasses, along with identification of at-risk areas and populations.

The good news, for us if not for the deer, is that there is no evidence chronic wasting disease can spread to people or domestic animals. Still, authorities recommend visitors to the park stay away from sick or dead animals (always a good idea, stay away from the live ones too while you’re at it) and alert the National Parks Service.

Prepare for the rise of zombie animals with Zoombies, streaming now on Peacock.

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