We know CWD is spreading among the deer population, and similar prion diseases are present in other species, most notably cows and sheep. But can humans get it? Is it safe to come into contact with a CWD-positive deer? What about eating CWD-positive meat?
Recent Scare Says Yes, Maybe?
There was a big splash in the news recently when two hunters died after consuming CWD-infected venison. Read about it here. Though most news outlets were careful to say this doesn’t prove CWD can be passed from deer to humans, this seemed to be some anecdotal evidence that it could happen. The two men ate CWD-infected meat, then they developed symptoms consistent with those that CWD-positive deer exhibit. Then they both died. Concerning to say the least.
Scientific Studies Say No, Very Unlikely
The results of a new NIH-backed scientific study were recently released that give us some more scientific answers. Scientists recently concluded the study and published their results in Emerging Infectious Diseases. The research suggests a significant species barrier that likely prevents the transmission of CWD from deer, elk, and moose to humans. These findings also align with decades of similar research using animal models by the NIH’s National Institute of Allergy and Infectious Diseases (NIAID). You can refer to the paper published on the study here.
Understanding Prion Diseases
Prion diseases are severe degenerative disorders affecting some mammals, primarily targeting the brain but sometimes impacting other organs like the eyes. These diseases occur when abnormal proteins fold incorrectly, aggregate, and prompt other prion proteins to misfold, ultimately damaging the central nervous system. Unfortunately, there are currently no treatments or preventive measures for prion diseases.
Why This Study is Different
Historically, researchers have relied on animal models like mice, hamsters, and monkeys to study prion diseases, often monitoring them for over a decade. In 2019, NIAID scientists innovated a human cerebral organoid model to study Creutzfeldt-Jakob Disease and explore potential treatments. These organoids, small spheres of human brain cells grown from skin cells, mimic the brain tissue's organization, structure, and electrical signaling, making them the closest available laboratory model to the human brain. They have been instrumental in studying various nervous system diseases, including Zika virus infection, Alzheimer’s disease, and Down syndrome.
Key Findings of the CWD Study
In the latest CWD study conducted between 2022 and 2023, the research team first validated their model by successfully infecting human cerebral organoids with human CJD prions, establishing a positive control. Then, they exposed healthy human cerebral organoids to high concentrations of CWD prions from white-tailed deer, mule deer, and elk. They then observed the samples for up to six months, and none of the samples showed any sign of infection.
These results suggest a substantial barrier to CWD prions infecting human brain tissues, even under direct exposure. The researchers caution that there are limitations to their study, such as the possibility of a small number of people having genetic susceptibilities that were not considered and the potential emergence of new prion strains with lower transmission barriers. However, they remain optimistic that the current data indicate humans are extremely unlikely to contract a prion disease from consuming CWD-infected deer meat.
So we’re safe, right?
This is good news for those of you who are worried about gutting a deer and then a month later having your brain melt a little. It’s important to mention though that we still don’t know more than we do know about CWD. We’re still learning. This study is an important piece of data, but it’s a single study that I hope will be followed by others. This is what we know so far and it should not be confused with a position that we now know everything.
So it’s safe to eat CWD-positive meat then? It probably is, yes. But I wouldn’t. This research definitely brings a certain level of confidence that the risk of CWD jumping to humans is minimal and unlikely, but I still think it’s prudent to have some vigilance, and maybe a little common sense too. For now though, I think we can rule out the zombie apocalypse from CWD.
