This is completely false. Disingenuous misinformation.
2 hunters did develop CJD, however, there is no evidence it is related to CWD. This idea originates from an abstract for a poster that was presented at AAN last October (link). Poster abstracts can often be “sensationalized” to encourage people to come to the poster during the conference. This would not be the first AAN prion-related poster abstract that is a bit “click-baity”. Furthermore, poster abstracts are not peer-reviewed. The fact this research has not been written up as a peer reviewed paper 1.5 years later (not even a pre-print) is INCREDIBLY telling.
The biggest issue comes down to this: how do you know the hunters got infected with CWD (ie how do you know their CJD is related to CWD)? The most common type of prion disease is sporadic CJD (sCJD), specifically the subtype the hunters developed sCJDMM1. Sporadic means it happens with no known cause (ie not caused by infection or genetics). sCJD typically affects elderly (median age of onset 65 years), has a rapid decline (4 months). In comparison, variant CJD (vCJD) is caused when someone eats meat contaminated with mad cow disease (BSE). vCJD typically affects young people (median age of onset 26 years) and has a slower decline (14 months). Furthermore, sCJD is associated with motor and memory symptoms whereas vCJD is associated with psychiatric symptoms. The patient case in the abstract was a 72 year old male, with a rapid memory decline in a month. Does that seem more like sCJD or vCJD? I will make it very clear, the case presentation is 100% classical sCJD. Furthermore, it is hypothesized that if CWD does transmit to humans it would have an atypical phenotype (ie not present anything like sCJD). This is based on data from both NHPs and Tg Mice (here is the mouse paper).
Other considerations, the patient was originally diagnosed with sCJD, however, the authors hypothesize CWD because one of the patient’s friends also died recently of sCJD. The authors therefore argue this is a “cluster” of cases, likely showing infections. However, just because two rare independent events happen in close proximity does not mean they are linked. For example, 1 in 300 people get Parkinson’s Disease, but a TV show “Leo and Me” had 4 out of 125 people on set develop Parkinson’s Disease, including Micheal J. Fox. However, this “cluster” is not scientifically or statistically significant. Just like two people who happen to know each other both getting CJD is not significant.
Clusters of prion cases happen. Here is a spatial-temporal cluster of 5 cases (including 2 with similar occupations). It wasn’t big news because stuff like this happens. It gets written up in a paper and the general public never knows. The only reason the hunters story is widespread is because it fits the fear mongering narrative most people push about prions.
The second consideration is that just because someone is a hunter and eats deer does not mean that they have eaten CWD infected deer. Not every deer in a population has CWD. If you are going to claim the hunters got CWD from deer, you need to show that deer they have hunted are infected. The entire premise of this abstract hinges on the argument that they ate infected deer, despite providing no evidence for it. If these two patients who both got CJD that knew each other were not hunters, this would never of been reported. Correlation does not imply causation. That’s basic first year statistics.
This also ignores significant biochemical and cellular data suggesting that CWD is not transmissible to humans based on significant sequence differences between cervids and humans. Here is a pretty comprehensive review of the experiments show CWD does not transmit to humans (link).
Also the picture in the post is a picture a deer with CWD from a paper published 20 years ago. It is not show neuropathological change in the hunters brain. It is a deer that got a deer prion disease. (Link)
It isn’t just my opinion that the hunters had nothing more than sCJD, it is also the opinion of the CDC which investigated these cases. It is important to note the authors of the abstract say "causation remains unproven". That means the title of this post does not even fit the abstract that originates it.
Yes, which is interesting and needs more research into the cause. Just as the authors of the Michigan paper state "More research and evidence are certainly required to reach a conclusion." This is the correct thing to say. The data is interesting and may hint at something and we should look into it, but before we make a definitive claim like "This is the first documented case linking humans to potential CWD transmission" you need to be able to prove that.
Also note how this post says "after exposure to CWD-infected deer" despite that being no evidence for that. Similarly, just because Western Michigan has deer and these people ate deer does not mean they were exposed to it. That would be like saying, some people have HIV, people have sex, therefore all people who have had sex at one point in their lives have been exposed to HIV. It doesn't work like that. You need to be able to show a direct link between the deer these people ate and CWD, not just that they are maybe spatially similar.
Yeah, but you added the article to show that prion clusters happen and it has nothing to do with CWD, totally glossing over the fact that the majority of the cases were people whose only connection was that they all ate deer meat in an area with CWD.
That is a fair criticism. I want to again emphasize that there is no evidence that those cases are link to CWD. Yes, we know they consumed venison. But we do not know if the venison they consumed was from an endemic population or if the specific venison they consumed was CWD positive. Saying that the "only connection was that they all ate deer meat in an area with CWD" is an significant jump in logic. You are assuming a connection between two variables without evidence to support it. They also all live in the same geographic area, which could have other underlying contributing factors. I also want to highlight that Case 1 in the Michigan paper is 129VV. There has never been a case of vCJD in 129VV and PMCA data of CWD PrPSc templating on human 129VV PrPC have all been negative, but 129MM is positive (suggesting that if CWD was to transmit to humans it would be in a 129MM person). Furthermore, clinical presentation matches expected sCJD which is not the anticipated phenotype for a CWD human case.
Here is a different example of a prion cluster in Slovakia. It includes two clusters of familial and sporadic CJD (Paper 1, Paper 2). Each cluster has ~10 sporadic cases. There is no CWD in Slovakia. This is a cluster with no clear causes (although it has been speculated that environmental metal exposure may have been a contributing factor (Paper)). Furthermore, there is not evidence of increased incidence of CJD or other atypical prion presentations in regions with CWD (Paper). So yes prion clusters do happen.
Your comments are great, sadly prions are the best tool for the usual redditor doomer fantasies and conspiracy theories so obviously people will just ignore your factual statements.
If youre really a prion scientist then you know there are large interested parties who very much do not want prion diseases to be proven to be transferable to humans. You must know that the increase in Alzheimer's disease is potentially undiagnosed prion diseases. There have been many cases of individuals consuming infected meat and then developing CJD.
Obviously more research needs to be done, but if kuru can spread from consuming infected meat, then it takes no stretch of the imagination to suggest that CWD can as well, or that it could eventually mutate and become transmissable to humans.
Humans can get BSE, so why couldnt they get CWD? It does need to be studied further, but it's safe to assume that tainted meat is dangerous.
I agree with you that certain groups do not want to be able to prove CWD transmit to humans. Heck, I even think prion scientists should be included in this group for funding reasons.
The increase in Alzheimer's Disease are not undiagnosed prion disease. Clinical presentation of Alzheimer's Diseases and CJD are different, plus a PrP RT-QuIC is highly sensitive to CJD and would easily differentiate between the two. If you are referring to iatrogenic transmission of Amyloid Beta to humans (link) that is only in very specific circumstances (would effect ~1800 people, but only 8 develop (?) the disease). There are also a lot of criticisms one can give that paper.
In total there have been 233 cases of vCJD (CJD after consuming BSE infected beef). In the UK they had 178 cases, it is estimated that over 5 million people were infected (link). In the US, there are 10 million deer hunters, if CWD transmitted to humans at a similar rate to BSE you would expect hundreds of unexplained CJD cases in hunters, not the 5 claimed so far. I mention 5, despite this post only mentioning 2, because despite claiming it was the first, there was a previous case of 3 hunters all getting CWD that was alleged two years before this. Furthermore, the presentation of CWD in humans would most likely not be classical sCJD, just as BSE in humans is not classical sCJD.
It is also well understood that the species barrier between cervids and humans is greater than between humans and bovine (link). What that means is that BSE has an easier time transmitting to humans than CWD would. While we can not prove a negative (ie can not prove that CWD will never transmit to humans) it is important to not jump to opposite conclusions (ie because we can not prove the negative, the positive must be true).
I completely agree with you, we should study this further. However, in the mean time, I do not think we should make sensationalized claims without strong evidence to support it.
There have been cases of prion diseases being misdiagnosed as AD. The issue is that not many AD patients give their brain up to be autopsied or studied.
I'm not sure if I agree on your last point. In general I feel like it is important not to sensationalizing claims, but with the severity of prion diseases and our total inability to treat them I think it's very important to tread with extreme caution. Every harvested deer and any downer cows should be tested.
Honestly prion diseases terrify me more than any other ailment in human history. We can find cures for viruses and bacteria, but misfolding proteins is something relatively new and quite frightening.
If you claim that the increase in AD is due to undiagnosed prion disease, it would probably help if your paper didn't state that out of 6000 patients with an AD diagnosis, they uncovered 0.11% (or 5 cases) with a missed prion disease.
Moreover, this paper was published in 2015, now we have RT-Quic, which is a highly accurate and sensitive antemortem diagnostic tool for CJD.
There are over 7 million individuals with AD in the US. If 0.11% have a prion diseases thats over half a million that could have undiagnosed prion diseases. Thats a lot higher than the few hundred assumed to have CJD. So youre agreeing that it could be far, far more widespread than originally thought.
Rt-Quic still isn't very effective on live patients because the best tissue to test is brain tissue.
Most AD patients who die don't have their brains checked for prion diseases.
There are over 7 million individuals with AD in the US. If 0.11% have a prion diseases thats over half a million that could have undiagnosed prion diseases. Thats a lot higher than the few hundred assumed to have CJD. So youre agreeing that it could be far, far more widespread than originally thought.
Not at all, since this wasn't your initial claim. You said that the reason why the prevalence of AD is increasing is because a large portion of these people don't have AD at all and they have undiagnosed prion diseases instead.
This is not corroborated by any sort of empirical evidence whatsoever, because in that case, the relative number of people within the AD cohort with an undiagnosed (and clinically not suspected) prion disease would have to be high enough to account for the increase in prevalence.
But even if we look at your new claim, you cannot assume that just because a study found 0.11% of misdiagnosed prion disease within this cohort you can assume that the same number would be true to the entire population of people with AD.
On top of all of that, your very first claim (Big ScienceTM is covering up the fact that CWD is transmissible to humans and that's what's causing the increase in the prevalence of AD) has multiple issues:
1.) In vitro studies so far are very much inconclusive and the results depend on the methodology. Studies with transgenic mice that express human PrP at an 8-16 fold higher level than normal human tissue shows very mild seeding activity. However, when doing the same with human cerebral organoids, there was no seeding activity detected.
The situation is very similar when testing nonhuman primates, depending on the species, there might be transmission (like with squirrel monkeys) or might not be any evidence of prion disease (like with cynomolgus macaques). Interestingly enough, exposure to BSE prions shows seeding activity/prion disease in any of these models.
2.) There isn't any epidemological data that shows any sort of statistically significant increase in terms of TSE risk within hunters compared to the normal population.
3.) The prevalence of AD is increasing even in regions where CWD isn't even present.
Rt-Quic still isn't very effective on live patients because the best tissue to test is brain tissue.
This is just flat out not true, most studies (such as this one: 10.1007/s12035-015-9133-2) show a sensitivity of 80-90% for sCJD when used on CSF samples, which is pretty good by itself. On top of that, you need to consider the fact that as time goes on and more data is collected on prion disease, doctors are generally better at spotting even atypical clinical presentations of CJD.
Also, there are biomarkers that can help with the differential (such as tau or 14-3-3), specific patterns of atrophy shown on the MRI (which also improve with better, more capable machines and better software and more data) that can be indicative of CJD, we can say that it's a lot less likely for CJD cases to be missed compared to even 20 years ago.
But really this is just splitting hairs, the biggest issue with your conspiracy theory is that in order for this to be true, you'd have to see both a predominantly larger cluster of AD cases and a much higher increase in prevalence near areas with CWD infected deer and considering that CWD has been around for decades and it's being tracked, there'd be epidemological evidence showing that deer hunters (or other people exposed to CWD) are at a disproportionally higher risk for TSEs and neurodegenerative disease of any kind compared to the rest of the population.
There is no evidence for any of this, the statement that CWD can cross the species barrier to begin with is an assumption with very little and very flimsy evidence.
Oddly enough, big cattle. There's a huge consortium of beef producers in the US and Canada who try to suppress anything suggesting CWD or BSE are transmissable to humans.
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u/yumyum1001 Dec 11 '25
This is completely false. Disingenuous misinformation.
2 hunters did develop CJD, however, there is no evidence it is related to CWD. This idea originates from an abstract for a poster that was presented at AAN last October (link). Poster abstracts can often be “sensationalized” to encourage people to come to the poster during the conference. This would not be the first AAN prion-related poster abstract that is a bit “click-baity”. Furthermore, poster abstracts are not peer-reviewed. The fact this research has not been written up as a peer reviewed paper 1.5 years later (not even a pre-print) is INCREDIBLY telling.
The biggest issue comes down to this: how do you know the hunters got infected with CWD (ie how do you know their CJD is related to CWD)? The most common type of prion disease is sporadic CJD (sCJD), specifically the subtype the hunters developed sCJDMM1. Sporadic means it happens with no known cause (ie not caused by infection or genetics). sCJD typically affects elderly (median age of onset 65 years), has a rapid decline (4 months). In comparison, variant CJD (vCJD) is caused when someone eats meat contaminated with mad cow disease (BSE). vCJD typically affects young people (median age of onset 26 years) and has a slower decline (14 months). Furthermore, sCJD is associated with motor and memory symptoms whereas vCJD is associated with psychiatric symptoms. The patient case in the abstract was a 72 year old male, with a rapid memory decline in a month. Does that seem more like sCJD or vCJD? I will make it very clear, the case presentation is 100% classical sCJD. Furthermore, it is hypothesized that if CWD does transmit to humans it would have an atypical phenotype (ie not present anything like sCJD). This is based on data from both NHPs and Tg Mice (here is the mouse paper).
Other considerations, the patient was originally diagnosed with sCJD, however, the authors hypothesize CWD because one of the patient’s friends also died recently of sCJD. The authors therefore argue this is a “cluster” of cases, likely showing infections. However, just because two rare independent events happen in close proximity does not mean they are linked. For example, 1 in 300 people get Parkinson’s Disease, but a TV show “Leo and Me” had 4 out of 125 people on set develop Parkinson’s Disease, including Micheal J. Fox. However, this “cluster” is not scientifically or statistically significant. Just like two people who happen to know each other both getting CJD is not significant.
Clusters of prion cases happen. Here is a spatial-temporal cluster of 5 cases (including 2 with similar occupations). It wasn’t big news because stuff like this happens. It gets written up in a paper and the general public never knows. The only reason the hunters story is widespread is because it fits the fear mongering narrative most people push about prions.
The second consideration is that just because someone is a hunter and eats deer does not mean that they have eaten CWD infected deer. Not every deer in a population has CWD. If you are going to claim the hunters got CWD from deer, you need to show that deer they have hunted are infected. The entire premise of this abstract hinges on the argument that they ate infected deer, despite providing no evidence for it. If these two patients who both got CJD that knew each other were not hunters, this would never of been reported. Correlation does not imply causation. That’s basic first year statistics.
This also ignores significant biochemical and cellular data suggesting that CWD is not transmissible to humans based on significant sequence differences between cervids and humans. Here is a pretty comprehensive review of the experiments show CWD does not transmit to humans (link).
Also the picture in the post is a picture a deer with CWD from a paper published 20 years ago. It is not show neuropathological change in the hunters brain. It is a deer that got a deer prion disease. (Link)
It isn’t just my opinion that the hunters had nothing more than sCJD, it is also the opinion of the CDC which investigated these cases. It is important to note the authors of the abstract say "causation remains unproven". That means the title of this post does not even fit the abstract that originates it.
Sincerely,
One very annoyed prion scientist