Alarm has been raised in the US because of a disease that affects the nervous system of deer and which can be dangerous even for humans, as although it is not yet clear whether it affects them, there are studies that raise concern.
As the New York Post reports, despite ongoing efforts to limit the spread of the disease in the U.S. and abroad, the deadly chronic wasting disease (CWD) remains a threat — with no vaccine or cure.
In 2005, the disease known as “zombie deer” disease, which makes them look like zombies, struck New York after several deer infected with CWD escaped from a fenced enclosure in Oneida County, a largely rural region in the north of the state.
Only a swift and aggressive cull operation by the New York Department of Environmental Conservation – resulting in the culling of hundreds of deer, with the cooperation of local hunters – was able to halt the outbreak.
Studies raise concerns that there may be a risk to humans as well
However, CWD continues to spread worldwide—including a recent outbreak in Yellowstone National Park—and many areas of the country are on alert for the disease in both wild and domesticated animals.
The chronically debilitating disease is known to experts as prion diseases, a group of rare progressive neurological disorders that affect humans and animals.
Other prion diseases include Creutzfeldt-Jakob disease and bovine spongiform encephalopathy, also known as “mad cow disease”.
The disease causes sponge-like holes to develop in an infected animal’s brain while affecting the cerebrospinal fluid and other body tissues.
What studies have shown
Although there have been no cases of CWD spreading to humans, some studies suggest that it poses a risk to certain species of primates that come into contact with the body fluids of infected animals.
“These studies raise concerns that there may be a risk to humans as well,” the US Centers for Disease Control and Prevention (CDC) said in a 2021 report.
That same year, Pennsylvania reported an outbreak of CWD in deer just a few miles from the New York State border. In November the CDC reported that the disease has been detected in 31 states, as well as three Canadian provinces, northern Europe and South Korea.
Prion diseases such as CWD have a long incubation period, which is particularly concerning because an infected animal may appear healthy for two years before showing symptoms, during which time it can spread the disease to other animals.
CWD and other prion diseases are spread through bodily fluids and through contaminated soil, plants, food or water. As the disease progresses to the brain and nervous system, infected animals may show symptoms such as:
- significant weight loss
- stumbling and lack of coordination
- excessive thirst or urination;
- ear drop
- lack of fear of people
Recommended preventive measures
- Hunters are asked to be on the lookout for deer, reindeer or other members of the mammal family showing any of these symptoms.
- Additionally, anyone dressing, skinning, or slaughtering animals for meat should wear nitrile, rubber, or latex gloves.
To control the spread of CWD, New York and most other states have adopted strict regulations against the importation of live deer and other game animals from out-of-state countries and areas, as well as bans against the importation of carcasses and offal.
People are also not allowed to feed wild deer because most human foods are unhealthy for deer and because congregating animals in one place to feed them can help spread CWD.