Chronic Wasting Disease, CWD, is an infectious disease that affects animals in the Cervidae, or deer, family. CWD is always fatal and can affect animals in the wild and in captivity. While this disease is not new, it has spread to 26 U.S. states since its discovery in the 1960’s.
CWD is closely related to Mad Cow Disease. The disease is not caused by a virus or bacteria. CWD is one of a family of diseases called transmissible spongiform encephalopathies. These diseases are the result of a naturally occurring protein, called a prion, that becomes misfolded and thus resists being broken down by the body the way normal proteins are.
The disease has been found in deer, elk, moose, and reindeer in the U.S. and Canada. CWD can be transmitted through direct animal contact, saliva, feces, infected carcasses, and through contaminated soil. Scientists have found evidence of CWD in soil 2 years after the infected animal was removed.
A notable increase in the geographic spread of CWD has taken place in the past two decades. In 2000, CWD was documented in five US states and one Canadian province; in 2010 it was identified in 17 states and two provinces; and in 2019, it was found in 26 states and three provinces. CWD has also been documented in South Korea, Finland, Norway, and Sweden.
The increase in cases of CWD has led to many states to regulate the transportation of deer. The lack of a uniform policy or awareness of existing policies makes it likely that deer infected with CWD are being harvested and transported to areas without current monitoring of the disease.
It is believed that baiting and feeding deer with corn piles, deer blocks, or other attractants can encourage the spread of CWD. Creating common feeding sites for deer can bring outside deer into new communities, risking the spread of CWD.
Currently, there have not been any cases of CWD transmitted to a human. But, laboratory studies have shown that the CWD infective prions can morph into a form that may be infective to humans, and it has been shown that other primates (macaques) can contract the disease by consuming meat from CWD infected deer. It is recommended that humans not consume meat from infected animals.
Written for Passport Health by Brittany Evans. Brittany is a freelance writer and photographer in North Carolina. She has a passion for the outdoors, health information, and travelling. You can find her at her website.