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purpleflame1257
dnautics
This comment is spot on (I'm a former prion researcher).
cogman10
What do you make of CWD?
That one scares me more than current known human prion disease. Mainly because it seems to spread really easily. Other prion diseases seem to practically require cannibalism to spread.
dnautics
Cwd is essentially the same as bse and cjd and scrapie. It's actually the one that you have to worry about the least. For unknown reasons, there is not species crossover between deer and cow/sheep/humans (I was briefly investigating the molecular mechanisms for this but finished my phd before getting results).
As for why the grazing animals can spread prion, my guess is that the prion protein is highly concentrated in the tongue, and grazing animals are likely to be able to pass the protein down to the ground via the saliva. Scrapie and bse are cross-transmissible
Incidentally, you probably shouldn't eat beef tongue.
CountDrewku
CWD hasn't jumped to humans ever, correct?
nikartix
How old are these proteins? If the do spread and remain dormant in soil they would have been a threat for entire existence of life on this planet. Exponential growth would only cause every place, especially a bio-reach locations to be full of it as food chain making more and more of the protein and animals remains are not handled in any way in the wild.
dnautics
They're old. Yeast have genes that transmit information generationally via the same mechanism. Probably the same "exponential" mechanism is involved in diabetes, alzheimer's, melanin storage (not a disease, the actual normal process).
Proteins, eventually degrade, even prions. We probably have an enzyme that accelerates degradation of them (my bet is it's insulin-degrading enzyme).
AnimalMuppet
I don't think proteins will live forever in the wild. Between bacteria, fungi, and just oxidation, I'm pretty sure a protein just sitting out there on its own is going to have a finite half-life.
chasil
It appears that the first mention of scrapie in scientific literature is 1755, and the disease increased with inbreeding (and lessened when this practice was stopped):
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1114482/
The wiki also indicates that a sheep vaccine distributed in 1935 caused an epidemic, as it contained contaminated neural tissue:
https://en.wikipedia.org/wiki/Scrapie
It also seems to me that the recent mRNA vaccines could be repurposed to target a section of a prion, so the immune system could clean them from the blood. An interesting question would test mRNA vaccine effectiveness in the cerebrospinal fluid, where microglia would be required to perform this function, as macrophages (and friends) are not present there.
eggy
Curious, I had heard of research where the brain of a sheep that was infected with a prion disease (not sure which), was burned to ash, and that ash placed on the exposed brain of a healthy sheep (via trepanation?), and it also developed the prion-caused disease. Is this anecdotal nonsense, or is it close to a real study done on prion diseases? Thanks!
dnautics
That's real. Moderately high temperatures do not effectively destroy prions/amyloid.
Note that "burning to ash" is not that hot.
aeternum
What are your thoughts on the risks of AlphaFold and prions?
It seems like prions don't have much chance to evolve/mutate naturally since any change makes them unable to duplicate. However with these simulation systems, are man-made prions a concern?
dnautics
> naturally since any change makes them unable to duplicate.
That's not true.
Don't worry about alphafold. Even if it's a really good extrapolation engine (and not a really good interpolation engine) the amyloid fold is unusual enough that I doubt that alphafold can heuristically solve structures much less assess energetic or kinetic factors (which is not what it was designed to do). Note that I am an alphafold optimist and am on record here saying that I consider alphafold to have solved the basic protein folding problem. More to the point, we don't have many reliable solved structures of amyloid folds, it's clear that they are heterogeneous anyways, and iirc no one has bootstrapped an infectious prion in vitro, which means we don't know exactly what makes something infectious... We can make prion amyloid in vitro but it isn't infectious unless it was seeded by an infectious prion amyloid.
falcolas
Globalization is a fairly new thing (on the 3.5B year timescale at least), allowing for the spread of any disease quickly. Whereas isolation and evolution has saved us in the past, it might not have the necessary time in the future (imagine if Covid had been even more deadly, for example).
masklinn
Prions don't really spread on their own though, yes they are extremely hardy and can survive in soils but that doesn't do anything, if it did and isolation was the only solution we'd have thousands of prion-infested red zones where humans couldn't set foot.
> imagine if Covid had been even more deadly, for example
It'd have been taken more seriously, and it would have had a higher chance of burning itself out. Covid's such a pain in the ass because it hits such a sweet spot, of spreading fast, being highly infectious, and being benign enough (with many of the infected spreading it asymptomatically). For the hell that it is, the one "saving grace" of Ebola is that it debilitates and kills fast enough it's very hard for it to spread, especially as it doesn't have great transmission vectors.
im3w1l
What I remember from middle school biology is that nutrients flow in a cycle. Organic matter in the soil will be composted and consumed by earth worms, funghi and microorganisms.
And to them, prions are just organic matter like any other.
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ravi-delia
In addition to the points other people made, proteins are really a whole different thing from viruses in terms of numbers. You make so many proteins every moment, at this point every possible screwup has been cooked up somewhere.
andy_ppp
If COVID were more deadly like Ebola it tends to not have long gestation periods where it can be spread without symptoms.
est31
tends to is not going to cut it in this instance. If 99% of diseases are either easy to spread, or deadly, we still need to worry about the 1% that are both. It only takes one such disease to cause a wipeout like event.
jMyles
If COVID19 had been significantly deadly, presumably it would have burned out at the pace of SARS1.
It seems to be close to the sweet spot in terms of being able to spread but still occasionally kill.
beiller
If it was more deadly it would spread less quickly. That's how diseases work from my vague university memories of an epidemiology course. They are on a spectrum of deadly to contagious.
derekp7
What actually causes this though? For example, take something like HIV that takes a long time to show symptoms, but have an airborne version of it. Do the things that make viruses airborne also keep them from having a long gestation period and also highly lethal?
vanderZwan
Sure, but this does not in any way favor prions over other options.
bradrn
(Quick correction: PNG, not NZ.)
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tomphoolery
[flagged]
hannasanarion
Ban... prions?
Do you think that you can go to the store and buy prions?
Maybe we can also ban the common cold and HIV while we're at it.
hsuduebc2
I believe that was sarcasm my friend.
danesparza
Agreed. Prions almost strike me as an interesting boundary condition for stupid behavior. But if most of the world's meat supply becomes effected by prion caused diseases (think: Chronic Wasting Disease https://www.cdc.gov/prions/cwd/index.html ) then I think we truly might be in a tight spot.
Igelau
IIRC, BSE (Mad Cow) was spreading among cattle because the industry was using meat-and-bone feed from infected cattle. It was tainting the meat supply because captive-bolt guns spray more brain around than more traditional hammer-oriented methods of slaughtering beeves.
So yeah, cannibalism and brain spray. Stupid behaviors.
adrianN
Luckily humans can survive quite well without any meat at all.
odyssey7
I’m not sure this would save you. The deer get CWD by eating the grass other deer have been around. A zoonotic CWD would find its way into plant-based diets.
hourislate
The article suggests it's transmissible through plants and even air. You can't even sterilize surgical equipment under normal protocol to kill them.
It is basically a juggernaut.
danesparza
Agreed. What 2020 has shown us is that many humans can't cope with change well. This is what would cause us to be in a tight spot (IMHO)
Mordisquitos
So can deer.
rjsw
ITYM affected, not effected.
legitster
Prions are pretty scary, but I think there are a lot of things this article gets wrong.
- Prions are resistant to sterilization (since there is nothing to "kill"), but simple soap and water are still highly effective
- Prions don't "last forever". They can live in buried carcasses for a few years, but some studies have shown that even our existing sewage treatment processes already break down a lot of prions.
- While vegans might have some risk, meat multiplies the risk because of how it can concentrate prions. I have to imagine that vegans have an incredibly low risk profile for prions.
- Most importantly, viruses and bacteria innately "want" to spread. Prions do not have any biological mechanism for their own propagation - they are just an unfortunate mistake of nature. And this seems to be key why there has never been a massive prion outbreak.
If you were an anarchist rooting for the collapse of society, as this writer seems to pitching for, sure it seems like it might be a more likely vector than many.
Ericson2314
> Most importantly, viruses and bacteria innately "want" to spread. Prions do not have any biological mechanism for their own propagation - they are just an unfortunate mistake of nature. And this seems to be key why there has never been a massive prion outbreak.
I disagree here, and but it's not fatal to your argument. Anything that reliably reproduces "wants" to. Hell, I bet prions can evolve too on large enough time scales (heterogeneous induced refolding), so we can say they are alive. But sometimes the tortoise is too patient and the race ends before the hare tires.
gus_massa
The prions are not involved in the formation of new proteins, so it's very^100 difficult that they can evolve to create more efficient versions. [I try to not use "impossible" because life finds a way ...]
Virus instead use their own material as the original to make copies, so any new good or bad variation will be copied in the offspring, and they can evolve.
im3w1l
In order to evolve there has to be some kind of genetic information passed on to descendants. But for prions there is no such mechanism. A lower energy state is assumed and that's that.
enchiridion
There does not have to be genetic information for evolution.
Evolution only requires "descent with modification". DNA is a mechanism for this, but it is not necessarily the only one.
odyssey7
This got me wondering: what is the advantage of genetic information (DNA / RNA) over a self-replicating entity without those convenient molecules?
My impression is that DNA / RNA-based organisms have a high tolerance for changes to their DNA / RNA, such that many genetic changes won't cause them to lose their self-replicating ability. This is great for evolution.
Prions, on the other hand, seem like they would have a low reproductive tolerance for changes to their structure.
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Scandiravian
So prions are simply a result of entropy? Am I understanding that correctly?
barbazoo
> I have to imagine that vegans have an incredibly low risk profile for prions.
What do you reckon the risk profile of vegetarians would be? Are prions likely to end up in eggs and milk?
thehappypm
In general I think we should be trying to eat foods that are really biologically dissimilar to humans to avoid being sickened by our foods' diseases. Plants and fungi don't seem to cause pandemics. Mammals do (SARS, covid, swine flu, possibly Spanish flu). Birds can make us sick (salmonella). Fish, mollusks, insects, probably safer, parasites aside.
bb123
Does your second point suggest that we should avoid eating beef?
Scandiravian
I think there's better arguments than a risk of prion disease for cutting beef (or meat in general) from your diet - not sure if your comment is meant as a joke that I'm not catching, so I'll hold out on going into details unless you're interested :-)
bb123
Not meant as joke. I'm aware that there are lots of good reasons for not eating beef, I was wondering if prion exposure risk is one of them, as the meat/no-meat argument is one I try to revaluate regularly as new info comes to light. I eat beef once or twice a week as I have found it hard to get sufficient iron, protein, b12 and enough calories in general without it (and other meats). That and it tastes good, but I'm always receptive to new counterpoints.
legitster
I mean, there are a lot of reasons to not to. And I say that as a meat eater.
nefitty
For people who are intensely worried about prions, it seems that eating less meat will decrease their chance of exposure.
GlenTheMachine
So one of the oldest known prion diseases is a disease of sheep called scrapie. It is not transmissible to humans, thankfully.
It turns out that there is genetic resistance to it. There's a specific gene, of which there are two forms, called Q and R. If a sheep is Q-Q, it has no resistance. If it is Q-R is has some resistance. If it is R-R it is completely immune.
All of which is to say: we should not just assume that exposure to prions results in a 100% disease rate, nor should we assume that prion disease itself has a 100% mortality rate. Because the diagnosis for prion disease is clinical. In other words, we only know someone has the prion if they show signs of the disease. And we only look for the disease once someone starts showing significant signs of disease. But there is no test that shows that you ave been exposed, nor is there a test that shows you have been infected but that your infection is spreading so slowly that (say) prostate cancer or heart disease will kill you long before the prion does.
ortusdux
prion infections are always eventually fatal, there is no cure, and they are contagious.
The majority of research into prions happens post mortem, and is usually trying to pin down the cause of death. Statistically, there must be prions that are not lethal.
I'm reminded of the issues with people that work at pig processing plants, who had the job of blowing the brains out of the skull cavity with compressed air. Many were not issued proper PPE and ended up with a wide variety of symptoms.
https://www.twincities.com/2008/02/06/minn-to-question-25-mo...
Scandiravian
I think that's an interesting point. Do you have a source for your statement, that most of the research happens post mortem?
It makes sense to me that non-lethal cases wouldn't be discovered, as it's probably prohibitively expensive to screen for non-lethal/dormant infections. It could also be that the progression is so slow for most people, that they die from unrelated causes before the disease becomes a problem (this is pure conjecture on my part)
ortusdux
The first promising blood test for mad cow (vCJD) was developed in 2016. Prior to that, "The only current method to diagnose vCJD is to perform a biopsy or a postmortem analysis of brain tissue." (NIH 2017).
https://www.nih.gov/news-events/nih-research-matters/new-met...
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5538786/
Scientists have since developed a promising method that relies on analyzing the retina.
https://www.nih.gov/news-events/news-releases/scientists-ide...
Scandiravian
Thank you for the links - I look forward to reading the articles :-)
incrudible
I remember that in the 90s, when "mad cow disease" was dominating the headlines, it was predicted that there would be an exponential increase in cases, decades down the line. The same point about prions being virtually indestructible was being made, the same concerns about surgical equipment and blood donations were raised.
Suffice it to say, the prion disaster did not materialize, so I'm skeptical about the same story being repeated almost verbatim today. My guess is that prions aren't all that contagious after all, especially after basic food preparation measures.
ipython
The concerns about blood donations continue to this day. A few years ago I went to a blood bank event not even thinking about vCJD and was turned away because I happened to live in Europe for more than 6 months in the early 90s.
It is a bit unnerving to know you may or may not have a disease that there is no test for, and symptoms may not appear until decades later.
813594
You might want to check again to see if you’re eligible now. They ended some of these restrictions on blood donation in the summer of 2020.
ipython
Thanks! It appears that the new restrictions no longer apply to me. I’ll be off to give blood later this month.
incrudible
...out of "an abundance of caution".
> It is a bit unnerving to know you may or may not have a disease that there is no test for, and symptoms may not appear until decades later.
That's true for many neurodegenerative diseases. If that's unnerving to you, better stay away from WebMD...
hajile
Who knows. I'll give you an interesting thought.
There is NO single, conclusive test for Alzheimer's disease. The symptoms are almost identical to CJD (human mad cow) with the biggest differentiator being time from diagnosis to death. Even Amyloid-beta plaque buildup is often (though not always) noted in CJD patients [0][2]. Likewise the other Alzheimer's marker tau protein is also elevated in CJD patients [3]. I'd note that we don't actually know that CJD must progress over 1-2 years rather than a decade -- it is an observational assumption.
Between 15-30% of Alzheimer's diagnosed patients also don't have the normal Alzheimer's brain symptom (presumably amyloid buildup) either. Alzheimer's as cause of death was 17.6% in 2000, but is now 37.3% in 2020.[1] Because CJD is defined as killing quickly, it isn't even checked for in such cases (a kind of self-fulfilling prophecy if the diagnosis criteria aren't actually accurate). It doesn't help that cleanup of a contaminated area is time consuming and costly (not to mention potential negative press and panic).
This isn't a new idea, but perhaps those fears were somewhat true, but have been buried under our lack of knowledge of protein diseases.
[0] https://pubmed.ncbi.nlm.nih.gov/3092727/
[1] https://alz-journals.onlinelibrary.wiley.com/doi/full/10.100...
incrudible
> The symptoms are almost identical to CJD (human mad cow) with the biggest differentiator being time from diagnosis to death.
Ordinary CJD has a much lower median age of death (68 years) than Alzheimer's (88 years), but vCJD (the form that is believed to be caused by contaminated food) has a median age of death of only 28 years.
https://en.wikipedia.org/wiki/Creutzfeldt%E2%80%93Jakob_dise...
A surge in young or middle-aged dementia cases would likely not have fallen under the radar.
> Between 15-30% of Alzheimer's diagnosed patients also don't have the normal Alzheimer's brain symptom (presumably amyloid buildup) either. Alzheimer's as cause of death was 17.6% in 2000, but is now 37.3% in 2020.[1]
You have mistaken the rate of deaths (per 100,000) for the percentage. When judging this increase, one must consider that in the same timeframe, the mean age of the population has risen by 10% and life expectancy increased by more than two years.
hajile
> You have mistaken the rate of deaths (per 100,000) for the percentage. When judging this increase, one must consider that in the same timeframe, the mean age of the population has risen by 10% and life expectancy increased by more than two years.
Sorry, knew what I meant, but messed up what I typed. In any case, doubling the death rate per 100k is still much greater than the 10% age and 2-3% lifespan increase would indicate. Alzheimer's mortality had increased 16x between 79 and 91 (from a mere 857 to 13,768 in 1991[0]. The previous study I quoted above put the 2018 mortality at 122,019. Alzheimer's is now the 6th leading cause of death and continues to rise at a rapid rate.
> Ordinary CJD has a much lower median age of death (68 years) than Alzheimer's (88 years), but vCJD (the form that is believed to be caused by contaminated food) has a median age of death of only 28 years.
This is the crux of the problem.
We have experimental knowledge about this from kuru. The last patient displayed symptomatic kuru some 5 decades after the cannibalistic practices had stopped.
Do only young people eat meat? If all age groups eat meat at equivalent rates and infection rates in cattle are constant (believed to be around 1 in a million IIRC), then the median age should be the population median age PLUS a shift for however long it takes to become symptomatic.
Linkage is also important. How do we know that CJD and vCJD are different? We made that distinction arbitrarily and don't have evidence that "normal" CJD is not caused by external sources. Official vCJD cases are around 200 over the past 30 years, so there isn't exactly huge amounts of data to pull from either.
If CJD really did explode in the 80s-90s, then you would expect the older generation to become symptomatic at an older age than would be typical if the disease were common in the decades before.
There seems to be a connection with being vegetarian/vegan and alzheimer's but how much is due to not eating meat and how much is due to overall healthy lifestyle is hard to determine.
Something weird is going on with Alzheimer's disease and the legit explosion in cases over the last 30 years (both per capita and as cause of death in the elderly) give reason to wonder what weirdness is going on.
chasil
Here is another major difference:
"We know that the β-A4 amyloid of Alzheimer’s disease also derives from a normal host protein that in diseased people accumulates in the brain, but it does not have the ability to transmit disease to a healthy person. Why this difference?"
xenadu02
We have no idea if US Beef is infected. The USDA prohibits anyone from testing their cows and ended their spot-testing program (which was a joke).
So unlike Europe we never reckoned with the problem and don't know if it is currently spreading. For human exposure we would not yet be far enough along to know if the US Beef supply either is or was contaminated.
Personally I have basically stopped eating beef for this reason.
incrudible
It is estimated that hundreds of thousands of infected cattle entered the food chain in the 1980s. The total number of cases of vCJD is at less than 250 as of 2018.
Feeding practices that led to BSE have changed, the USDA is still testing for BSE, and if the disease was spreading, we'd probably notice it at some point.
Personally, I'd be far more worried about cattle farming practices spawning some sort of super-resistant flesh-eating bacteria than anything related to BSE.
mannerheim
Also worth noting that only four of those cases occurred in the US, and none of those have been traced to US beef; in each of these cases, the patients had spent a significant time living outside of the US (and two of the patients lived in the UK, whose cows were known for having BSE).
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whatshisface
>The USDA prohibits anyone from testing their cows
Huh? Why would they prohibit testing?
mannerheim
The USDA does test a sample of cows, but prohibits companies from doing testing on their own cows probably because the tests would likely be inaccurate and provide an unwarranted impression of safety:
> NOT A FOOD SAFETY TEST
> BSE tests are not conducted on cuts of meat, but involve taking samples from the brain of a dead animal to see if the infectious agent is present. We know that the earliest point at which current tests can accurately detect BSE is 2-to-3 months before the animal begins to show symptoms. The time between initial infection and the appearance of symptoms is about 5 years. Since most cattle that go to slaughter in the United States are both young and clinically normal, testing all slaughter cattle for BSE might offer misleading assurances of safety to the public.
> ...
> Why doesn't USDA test every animal at slaughter?
> There is currently no test to detect the disease in a live animal. BSE is confirmed by taking samples from the brain of an animal and testing to see if the infectious agent - the abnormal form of the prion protein - is present. The earliest point at which current tests can accurately detect BSE is 2 to 3 months before the animal begins to show symptoms, and the time between initial infection and the appearance of symptoms is about 5 years. Therefore, there is a long period of time during which current tests would not be able to detect the disease in an infected animal.
> Since most cattle are slaughtered in the United States at a young age, they are in that period where tests would not be able to detect the disease if present. Testing all slaughter cattle for BSE could produce an exceedingly high rate of false negative test results and offer misleading assurances of the presence or absence of disease.
> Simply put, the most effective way to detect BSE is not to test all animals, which could lead to false security, but to test those animals most likely to have the disease, which is the basis of USDA's current program.
The ban might not be warranted (I don't believe it is myself), but it is important to be aware that testing for BSE may not be accurate at the time most cows are slaughtered.
https://www.usda.gov/topics/animals/bse-surveillance-informa...
pm90
Because businesses don’t want to bear the loss (financial and likely reputational) of finding out that their beef contains prions.
ggreer
If US beef was contaminated, wouldn’t there be thousands of cases of vCJD[1] by now?
1. https://en.wikipedia.org/wiki/Variant_Creutzfeldt–Jakob_dise...
imglorp
Yes there could be. It remains latent for years after consuming the infected meat. Guess we'll find out! ¯\_(ツ)_/¯
mannerheim
It isn't really possible to prepare beef in a way to eliminate prions; you have to just make sure the beef you're preparing doesn't have them.
incrudible
I'm aware that prions are hard to destroy, but that's a different question as to whether they are contagious. A lot of contaminated beef did enter the food chain, yet the expected surge in vCJD did not occur. I would expect cooking to have some impact here, but that's just a guess.
JKCalhoun
> Ancient and odd but relatively easy to talk about, viruses are the perfect vector for the horrors peddled by the BBC, New York Times, and their ilk.
Proceeds to peddle the "horrors" of prions.
wrinkl3
Yeah I'm not a huge fan of the way the article is written. The concerns are undoubtedly real, but the pearl-clutchy tone and the endless barrage of asides and pop culture references make me doubt the author's conclusions.
geophile
This guy is trying really, really hard, wildly inflating our susceptibility, our risk, the vectors by which prions can be transmitted, everything. I hope I never sit next to him on a long plane flight.
anonu
That can be generalized to any journalist or media organization. Their currency is fear.
hannasanarion
What reputable journalist or media organization claims that the secret jewish new world order is using vaccines to inject people with prion diseases like this guy does?
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decasia
I for one would appreciate anyone who has expert biological knowledge commenting on this.
I don't entirely dismiss this article since I have a friend who worked with prions in a bio lab at the Univ. of Chicago and I remember he was absolutely terrified of them. (And IIRC he reported having some doubts about laboratory safety protocols...) But I don't think he was afraid of this kind of apocalyptic endgame either; he just thought they were horrendously nasty stuff.
balozi
The limited research there is on prions is heavily concentrated on the nasties. Its like learning about bacteria by studying Mycobacterium tuberculosis and coming to the conclusion that bacteria = death.
aprinsen
>The anti-globalist movement of the 90s is long dead. The far-left which fueled it has been co-opted, down to the level of its language and internalized identities, by global business interests. Coordinators of anarchist riots appear in Forbes; there are anarchist professors and journalists.
No citations
Lots of fear
Thinly veiled far right rhetoric
legitster
This article is coming from the far left, not right. I think he is bemoaning the lack of real anarchists.
But perhaps horseshoe theory strikes again.
Ericson2314
I understand the argument here, and how ill-prepared we are for steady low-coefficient exponentials, but never more have I felt like the 2nd law of thermodynamics is my friend.
Even if 1 prion can kill you, even if prions will survive in the soil indefinitely, I think we are going to erode all the topsoil faster than the prions can accumulate in concentrations sufficient to cause issues.
SquibblesRedux
As I read this, cellular automata lurked in the back of my mind. Despite the stochastic details, there is an eerie clockwork marching hiding under the covers of life.
cryptoquick
When you put it that way, it sounds oddly poetic.
SavantIdiot
> Prions Are Going to End the World
Get in line.
/* reads TFA about prions binding in soil */
Please move to the front of the line.
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Counterpoint: The Fore people of NZ had kuru from ritual cannibalism. Then they stopped. Eventually, the disease stopped too. Prions are nasty, but we've had 3.5 billion years of protein folding and none of it has ended the world yet.