A recent medical case report indicates that a deadly prion disease might have crossed from deer to humans. The report involves two hunters who died after consuming venison from a deer population known to be infected with chronic wasting disease (CWD), a fatal prion disease similar to bovine spongiform encephalopathy, or mad cow disease.
Chronic wasting disease, sometimes called “zombie deer” disease, is incurable and invariably fatal, affecting animals like deer, elk, and moose. It spreads through misfolded proteins known as prions, which can trigger surrounding proteins to misfold, ultimately leading to tissue dysfunction, especially in the brain. The spread of prions in humans results in a rare disease called Creutzfeldt-Jakob disease (CJD), which has been a cause for concern due to its similarity to mad cow disease.
Doctors at the University of Texas reported that a 72-year-old man died after exhibiting rapid-onset confusion and aggression. The man’s friend, who was a member of the same hunting lodge, also passed away after showing similar symptoms. The second man’s autopsy revealed that he had died from CJD, suggesting that chronic wasting disease might have made a zoonotic jump from deer to humans.
Chronic wasting disease spreads easily among deer, and evidence suggests that humans are exposed to it through consumption of infected venison. A 2019 study estimated that between 7,000 and 15,000 animals with CWD were being eaten every year, with that number expected to increase by 20 percent annually.
Despite the potential risk, there is no definitive evidence that these two men’s deaths were directly caused by CWD. Prion disease can also arise spontaneously, albeit rarely. The report did not specify where the two men lived, but CWD has been detected across North America, including at least 32 states in the US and throughout Canada.
Given the potential risks, the doctors caution that further investigation is needed into the possible human health implications of consuming CWD-infected deer. They suggest that clusters of sporadic CJD cases may occur in regions with CWD-confirmed deer populations, indicating a potential risk of cross-species prion transmission. Surveillance and ongoing research are critical to understand this possible link and its impact on public health.
The report, published in Neurology, highlights the need for caution and emphasizes the importance of vigilance in monitoring CWD and its possible effects on humans. The doctors call for further investigation to determine the exact causes of these cases and the potential risks associated with consuming meat from CWD-infected deer.