Already struggling to adjust to Colorado’s booming human population, wildlife in the Centennial State is facing another major issue – chronic wasting disease. Progressive and always fatal, chronic wasting disease could become a bigger problem than it already is if something isn’t done to prevent its spread. Here are 6 things you need to know about chronic wasting disease, or CWD.

1. Chronic wasting disease is already very prevalent.

While this could be the first time you’re hearing about “chronic wasting disease,” one data set revealed that it’s already infected up to 16 percent of tested male animals in certain parts of Colorado. Note: This disease also effects females, they just weren’t included in this specific sample set. Because chronic wasting disease is the result of a deformed protein called a prion, not a virus or bacteria, it’s particularly resilient, which can make it easy to spread.

2. Wasting disease symptoms pose severe implications.

Chronic wasting disease attacks the brain of infected animals, resulting in tremors, awkward head movements, repetitive walking patterns, salivation, and teeth grinding, among other things. The disease is progressive, meaning symptoms worsen over time, until death occurs as a final symptom. While late-stage symptoms are often obvious, early stage symptoms can be difficult to observe. This makes it difficult to cull infected animals from a herd before they’ve already started spreading the disease.

3. Chronic wasting disease has only been naturally found in cervids.

First discovered in 1967 in a mule deer, chronic wasting disease, or CWD, has only been found in cervids ever since. “Cervids” include animals like deer, elk, moose, and reindeer. While symptoms of chronic wasting disease have only been found in cervids, other types of animals are suspected for aiding in transmission, including various birds, thanks to the fact that CWD prions can pass through a bird’s digestive system intact.

4. Humans aren’t susceptible – that we know of.

While the most recent data shows that animals can’t transmit chronic wasting disease to humans, this concept is still something being studied. According to the official statement by the Center for Disease Control and Prevention, “more epidemiologic and laboratory studies are needed to monitor the possibility of such transmissions.” The CDC then went on to recommend that people avoid eating parts of animals known to house chronic wasting disease, such as the brain, eyes, and lymph nodes. The Colorado Department of Public Health and Environment has also released a similar statement acknowledging that there may be a “small risk.”

5. CWD can be spread in multiple ways.

Chronic wasting disease may be spread when a healthy animal comes in contact with an infected animal, an infected animal’s body tissue, or an infected animal’s saliva. Studies have also found a high rate of infection transfer from mother to offspring, with one study showing a rate of 80% transfer in the case of Rocky Mountain elk. Environmental factors are also expected to aid the spread of CWD, as CWD prions are known to cling to the dirt where they drop. Because of CWD’s ability to pass through a bird’s digestive tract, bird feces that lands on the ground, especially in roosting areas, can be very problematic for grazing herds that pass through the space next.

6. There’s no ‘magic bullet.’

Recently, the Colorado Parks & Wildlife Service has started to consider how they can combat the spread of chronic wasting disease. Among these ideas include having hunters test their kills to improve the state’s ability to track CWD, as well as targeting the bucks in herds where the disease is particularly prevalent. Additional measures of prevention include making sure that carcasses are disposed of properly. Simply leaving a carcass for the scavengers is quite dangerous, as this will leave the site of the carcass infected after the tissue is gone. Even burning an infected carcass won’t get rid of the dangerous prions. That being said, controlled burns have been suggested as a means of controlling the spread under the hypothesis that eliminating plants where the prion is may prevent healthy grazers from stumbling onto the area and getting the disease.

In Closing

While the always-fatal chronic wasting disease has only been seen in members of the family Cervidae, the severity of the condition and difficult early-stage diagnosis make CWD particularly dangerous. As of right now, there haven’t been any cases where the condition has been observed naturally occurring in humans (or any other non-cervid species). However, the CDC does acknowledge that more studies need to be done on whether or not transmission between infected animals and humans is possible. At the moment, it seems like only cervids should be worried, though expect the disease to be continually monitored and studied.

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