What Is Zombie Deer Disease And How Dangerous Is It?

A wild deer.
  • Zombie deer disease was first reported in Colorado in 1967
  • CWD is a prion disease which causes the proteins in the brain and spinal cord to fold abnormally, causing the animal to behave like a zombie
  • There is no cure or vaccine for the zombie deer disease
  • It is still not clear whether or not the disease can occur in human
  • 24 states in the US have reported cases of zombie deer

As of August 2019, zombie deer disease, also known as a chronic wasting disease (CWD) had been reported in 24 US states and two Canadian provinces. Scientists warned that the disease, which causes deer to lose weight and behave like a zombie, was spreading at an alarming rate in America and that it was too late to stop the spread. According to CDC, zombie deer disease was first reported in Colorado in the 1960s and has now become increasingly common in the Midwestern region, East Coast, and southwest region. Although the disease is a primary concern for wild animals like elk and deer at the moment, there is no evidence that it could have a direct impact on humans. However, little is still known about CWD.

Understanding The Disease

Zombie deer disease is a prion disease that affects mainly the cervids such as the mule deer, red deer, reindeer, elk, and moose. It is called a prion disease because it involves proteins whereby infectious proteins causes other proteins in the body of the animals to fold abnormally, especially the proteins in the spinal cord, brain, and other tissues. Prions cause a family of diseases known as transmissible spongiform encephalopathy (TSE) that include crappie and mad cow disease. It is still not clear why the prion proteins change in such a harmful way. Apart from the US and Canada, cases of CWD have also been reported in South Korea, Finland, and Norway.


CWD can lead to brain damage, excessive weight loss, and behavior change such as drooling, lack of body coordination, stumbling, excessive urination or thirst. The animals may also exhibit a lack of fear or aggression towards people. It is because of these characteristics that many people refer to the CWD as “zombie deer disease.” It is not always obvious when an animal has the disease because it can take up to one year to show the symptoms. The symptoms get even more serious as the disease progresses. The affected animal may also wander away from the herd into the open, exposing them to hunters.


Scientists are still not sure how zombie deer disease spreads, but are of the opinion that by drinking infected water or through contact with affected body fluid or tissue such as saliva, blood, feces, and urine. Once the disease is introduced in an area, it spreads very quickly to other animals. The death of an infected animal does not eliminate the disease completely because the risk of spread remains for a long time. The rate of CWD infection in the US is estimated to be as high as 10-25%.

Transmission To Human

There is growing concern that zombie deer disease could be transferred to a human. However, there is no evidence to support the concern. According to the CDC, there is no supporting evidence for the possibility of CWD spreading to humans. However, experiments have shown that the disease can affect macaque monkeys which have close genetic similarities with humans. It would be a disaster if zombie deer disease were to occur in humans since the disease has no cure or vaccine.

Zombie deer disease is a prion disease that attacks elks and deer. It results from the abnormal folding of the protein in the brain, spinal cord, and other tissues in the body of the animal, causing the animal to exhibit zombie-like symptoms such as rapid loss of weight, stumbling, aggression towards human, and lack of body coordination. There is no evidence to show that the disease affect human.


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