The state of Nevada is on high alert after reports of a “zombie deer" stealthily creeping towards their border.
Deers with chronic wasting disease (CWD), a highly contagious condition that causes zombie-like symptoms such as a lack of fear of humans, drooling, a lack of coordination, and emaciation, have been reported in 24 states in the US, according to the Centers for Disease Control and Prevention.
With infected deers creeping through neighboring Utah, Nevada is now desperately trying to ward off any infection from crossing into state boundaries. The Nevada Department of Wildlife is testing dead animals and keeping a close eye on elk and deer migrating across the border from Utah. A new bill has also tightened restrictions on elk, deer, or moose that hunters can bring into Nevada from neighboring states.
CWD is highly infections among deer, elk, and moose, but it’s not caused by bacteria, viruses, fungi, or even parasites. The infection is believed to be caused by abnormal proteins called prions. These infectious agents arise when normal proteins in the body are folded into the wrong shape. Not only do these twisted proteins lose their normal functions, but they also trigger a devastating domino effect to neighboring proteins and misfold them too.
Some of the more infamous diseases caused by prions are BSE, aka “Mad Cow disease”, and Variant Creutzfeldt-Jakob disease, which infects humans.
All of these diseases affect the brain and can lead to severe brain damage, changes in behavior, and difficulties with movement. They are also all currently untreatable and a real pain to deal with because they can have an incubation period of over a year, leaving them untraceable and running the risk of further transmission. As for CWD, scientists aren’t even too sure how it spreads between animals, although it’s thought to persist in the environment for some time.
The slippery nature of prion diseases means that keeping CWD at bay is a real struggle.
“It’s not a matter of if, it’s a matter of when. We know that we can’t wrap Nevada in a bubble," Peregrine Wolff, a wildlife veterinarian with the state’s Department of Wildlife, recently said during a public testimony, as reported by Associated Press
Scientists do, however, have a little bit more understanding of prion diseases in humans. Variant Creutzfeldt-Jakob disease is primarily transmitted by eating contaminated meat, such as BSE-infected beef.
Prion diseases were first described in the 1960s through the work of a young Australian medical researcher called Michael Alpers, who noticed a group living in the Eastern Highlands of Papua New Guinea suffered from a mysterious condition known only as “Kuru”. Alper eventually found out the group practiced a funerary ritual of cannibalism. These observations paved the way for the eventual discovery of prions as an infectious disease-causing agent.
In another curious prion disease case, a number of people from rural Kentucky developed Variant Creutzfeldt-Jakob disease in the late 1990s. As it turned out, all of these people had a history of eating squirrel beans, either scrambling them with eggs or putting them in a stew called “burgoo”.
Currently, there is no direct scientific evidence to suggest that CWD can be transmitted to humans. However, as a precaution, authorities recommend not eating any meat that’s come from a CWD-infected animal.