Humans should be prepared for a "slow-moving disaster" as a horrific zombie deer disease spreads across at least 32 states in America and parts of Canada.
The deadly disease, known as chronic wasting disease (CWD), leaves animals confused, drooling, and unafraid of humans. It was first discovered in November following a deer carcass testing positive for the disease in Yellowstone National Park in Wyoming.
According to the United States Geological Survey (USGS), the virus has been detected in 32 states and four Canadian provinces. The large majority of cases have been reported in the upper Midwest, as well as the mid-Atlantic states. Kansas, Nebraska, and Wisconsin have all reported cases of the virus. Dr Michael Osterholm has dubbed the disease a "slow-moving disaster" which has the possibility of spreading to humans.
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Dr Cory Anderson, the program co-director at the Center for Infectious Disease Research and Policy, believes thousands have possibly already eaten meat from infected deer. He told The Guardian: "The BSE (mad cow) outbreak in Britain provided an example of how, overnight, things can get chaotic when a spillover event occurs, say, from livestock to people.
"We're talking about the potential of something similar occurring. No one is saying that it's definitely going to happen, but it's important for people to be prepared."
Samples from the body of the infected deer tested positive for CWD multiple times, according to the Wyoming Game and Fish Department's (WGFD) Wildlife Health Laboratory. The testing of dead and alive animals includes taking samples from the creature's nervous system tissue, either from the central nervous system, like the spinal cord, or peripheral systems, such as the retropharyngeal lymph nodes and the tonsils.
Dr Anderson added the disease is "invariably fatal, incurable, and highly contagious" as it can cause weight loss, loss of coordination and other fatal neurological symptoms in deer and related species.
He said: "'Baked into the worry is that we don't have an effective easy way to eradicate it, neither from the animals it infects nor the environment it contaminates.' The US National Park Service said last month: "There is currently no evidence that CWD can infect humans or domestic animal species."
According to Centres for Disease Control and Prevention, studies have proved that the disease posed a risk to non-human primates including monkeys. 'These studies raise concerns that there may also be a risk to people,' the agency said. 'Since 1997, the World Health Organisation has recommended that it is important to keep the agents of all known prion diseases from entering the human food chain."
Following the discovery of the disease, Yellowstone authorities are revising their strategy for surveillance and dealing with more sick animals as CWD is “density-dependent”, meaning infection rates are higher where large numbers of animals come together.
Dr Thomas Roffe, a vet and former chief of animal health for the Fish & Wildlife Service, admitted: “There’s a lot at stake for the Yellowstone ecosystem and a lot at stake for all Americans who enjoy having healthy wildlife on the landscape.”