Disease monitoring in wildlife herds is critical to wildlife management and to identify potential zoonotic risks. New positive tests in Lancaster County, Pennsylvania, represent the latest in 46 positives since 2012. Although Chronic Wasting Disease (CWD) is a contagious fatal disease among deer and elk, research suggests that humans, cattle and other domestic livestock are resistant to natural transmission.
CWD is a transmissible neurological disease that produces small lesions in the brains of infected animals. It is characterized by loss of body condition, behavioral abnormalities and death, is classified as a transmissible spongiform encephalopathy (TSE), and is similar to mad cow disease in cattle and scrapie in sheep.
Source: CWD Alliance, February 12, 2018.
The Centers for Disease Control and Prevention report no strong evidence that humans or livestock can contract CWD. CWD attacks the brain of infected deer, elk and moose, producing small lesions that eventually result in death. Animals can get the disease through direct contact with saliva, feces and urine from an infected animal or contaminated environment.
Clinical signs include weight loss, excessive salivation, increased drinking and urination, and abnormal behavior like stumbling, trembling, and depression. Infected deer and elk may also allow unusually close approach by humans or natural predators. The disease is fatal and there is no known treatment or vaccine.
INSIGHTS: The map of Chronic Wasting Disease in North America helps visualize the risk of transmissible diseases.