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Doctors investigate mystery brain disease in Canada

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Re: Doctors investigate mystery brain disease in Canada

#271

Post by StanislavPetrov »

vkou wrote: post #222
shkkmo wrote: post #186

Earlier quoted context omitted.

That isn't what is happening. The USDA is prohibiting suplemental testing. The allegation is that this is because that might reveal cases of infection that would show the USDA testing policies are not sufficient. Thus the USDA is placing their reputation over the health of US citizens.

Another poster makes the argument that the USDA does not prohibit supplemental testing, it just prohibits making safety claims on the basis of supplemental testing. I find their argument far more persuasive than yours. Is there more to yours?

No, the USDA prohibited testing. The reason they offered for prohibiting the testing was purportedly their concern for false safety claims. They didn't merely prohibit what they consider to be misleading claims, they used their regulatory power to block the testing.

>It asked the USDA for permission to buy test kits from a California company that made the equipment in France. However, under the Virus-Serum-Toxin Act, the government can regulate the manufacturing and sale of “any virus, serum, toxin, or analogous product for use in the treatment of domestic animals.” The USDA deemed the “rapid BSE test” a “treatment” under the Act and banned Creekstone from buying test kits from Bio-Rad.

https://www.courthousenews.com/usda-can-block-testing-for-ma...

Re: Doctors investigate mystery brain disease in Canada

#272

Post by gojomo »

mannerheim wrote: post #257
gojomo wrote: post #252

Earlier quoted context omitted.

This is the same error the CDC & FDA made in the early stages of COVID, insisting on fussy rationed tests based on hand-wavy ideas about public misinterpretation. That error likely contributed to hundreds of thousands of preventable deaths by hiding initial community spread for a month or more. Mass testing, even testing that's mostly at a stage unlikely to detect anything, and only occasionally on less-typical older…

> Mass testing, even testing that's mostly at a stage unlikely to detect anything, and only occasionally on less-typical older animals, will provide new useful info. What useful information does it provide? Is there any evidence that testing can detect BSE before symptoms appear? Japan had tested clinically healthy cows until 2017, when they decided to limit testing to symptomatic cows.[0] > Waiting to test until an…

> What useful information does it provide?

The potential for surprise & early detection.

As your quote noted, most cows are slaughtered earlier, so generations could be infected without any detection. If you only test 5yo symptomatic cows, you can never find an outbreak until it's too late, or anything that contradicts the breezy reassurances of the industry-captured USDA.

Again, it's like when the CDC & Fauci were assuring people that there was no significant community COVID spread, when they were also blocking any testing that could detect such spread, by limiting tests only to those that fit their preconceived notion ("only recent returnees from Wuhan").

How much, if any, random surveillance of older asymptomatic cows happens that gives you such confidence in the current testing?

How many meat cows live long enough to get a good read on the symptomatic rate?

Are you sure early mild symptoms of ill health might not just get a cow culled before enough symptoms-to-test arrive, by ranchers who, like the USDA, "would rather not know"?

Your last paragraph seems to reduce to, "we'll know if there's a lot of it, if and when there are a lot of young people with suspicious BSE".

We should aspire to use something other than our young people for early detection. Or at least not block those who want to try it.

Re: Doctors investigate mystery brain disease in Canada

#273

Post by mannerheim »

gojomo wrote: post #272
mannerheim wrote: post #257

Earlier quoted context omitted.

> Mass testing, even testing that's mostly at a stage unlikely to detect anything, and only occasionally on less-typical older animals, will provide new useful info. What useful information does it provide? Is there any evidence that testing can detect BSE before symptoms appear? Japan had tested clinically healthy cows until 2017, when they decided to limit testing to symptomatic cows.[0] > Waiting to test until an…

> What useful information does it provide? The potential for surprise & early detection. As your quote noted, most cows are slaughtered earlier, so generations could be infected without any detection. If you only test 5yo symptomatic cows, you can never find an outbreak until it's too late, or anything that contradicts the breezy reassurances of the industry-captured USDA. Again, it's like when the CDC & Fauci were a…

> As your quote noted, most cows are slaughtered earlier, so generations could be infected without any detection.

They couldn't be detected by those tests anyway if they don't have symptoms, or at least not until shortly before symptoms become apparent.

> Again, it's like when the CDC & Fauci were assuring people that there was no significant community COVID spread when they were also blocking any testing that could detect such spread, by limiting tests only to those that fit their preconceived notion ("only recent returnees from Wuhan").

There are a number of differences here. Most importantly COVID tests can detect if you have COVID even when asymptomatic, but BSE tests cannot detect BSE before it is symptomatic.

> How much, if any, random surveillance of older asymptomatic cows happens that gives you such confidence in the current testing? How many meat cows live long enough to get a good read? Are you sure mild symptoms of ill health might not just get them culled before enough symptoms-to-test by ranchers who, like the USDA, "would rather not know"?

> Your last paragraph seems to reduce to, "we'll only know if there's a lot of it if and when there are a lot of young people with BSE".

First, the testing is of symptomatic cows, not asymptomatic cows, and it is deliberately not a random sample, but a sample of the population that is most likely to have it.

Second, my point is that the lack of any cases of young people with vCJD in the US, let alone widespread cases, indicates that it simply isn't the case that we have some phantom population of cows with BSE that are being let through by the USDA.

> Or at least not block those who want to try it.

I agree the USDA shouldn't block it. However, it isn't unreasonable to prohibit marketing based on the use of such tests if they give an unwarranted impression of safety; allowing that would be misleading advertising. When Creekstone applied to do testing, it was precisely for this reason that they applied, and for this reason they were denied.

Re: Doctors investigate mystery brain disease in Canada

#274

Post by userulluipeste »

codingbeer wrote: post #50
sirsinsalot wrote: post #24

Prion diseases terrify me. Especially having been in the UK eating beef at the time of the BSE outbreaks in the 1990s. I wonder if there have been studies on the scale of potential latent vCJD/Prion disease in the population?

Whenever a topic about something that could potentially destroy humanity comes up (say, climate issues), there is always some comment that makes a reasonable argument of why things are not as bad as they seem. This never happens when prions are the topic.

Prion caused disease is indeed terrifying on individual level but, from its impact over the species' survival, it isn't that menacing. The decay takes decades, which is enough for breeding the next generation. Human life expectancy may get shorter, which sucks, of course, but humans lived shorter lives for most of their history. So no, it's not that bad. Even assuming that the entire human population will get infected from young age with no way to avoid it, it won't be that bad. It would come with a bit of adjustment, like having to raise kids sooner because the luxury to postpone (for life enjoyment or other pursuits) won't be there, but things will go on.

Re: Doctors investigate mystery brain disease in Canada

#275

Post by peteretep »

regularfry wrote: post #253
thatguy0900 wrote: post #138

Earlier quoted context omitted.

I think the idea is that if you wanted to spice up a marriage with an affair, you could use this to "cheat" on your spouse with your spouse. Both parties would be consenting the whole time. One would just think they are cheating.

Oh, I understand the concept. It's broken. If I am "consenting", but not to the action that's actually happening, I am not, in fact, consenting. If I believe that I am consenting to sex with someone that's not my husband, in that moment I am not consenting to sex with my husband. If they then have sex with me, knowing that that is my state of mind , that is non-consensual.

You do not understand the concept:

I decide I want to try a bit of "something new", and I pay someone to induce a Capgras delusion in me. At which point, my wife seems like an imposter. I wish to have sex with this new person, and I am also sure my real wife has given me permission to, prior to this. You can tell me as much as you like that it's "really" my wife, but, in my delusion, I am quite sure it's just someone who looks like her, and delightfully and consentfully have sex with the imposter new person -- who is giving their consent the whole time -- with all the thrill that entails. Afterwards, the delusion wears off, and I realise it was just sex with my wife. Everyone has consented at every point to this.

Re: Doctors investigate mystery brain disease in Canada

#276

Post by eganp »

robbiep wrote: post #167
throwaway316943 wrote: post #123

Earlier quoted context omitted.

They can’t evolve independently but biological systems that produce proteins can evolve new proteins and new ways of manipulating proteins. A nightmare scenario would be a bacterial or viral mutation that produced a deadly prion.

A nightmare scenario for me is the creation of mRNA coding for a misfolded PRNP being weaponised.

This probably isn't possible as the folding of PrP is not encoded in the mRNA of PRNP. The fold of PrP is a post-translational phenomenon, much like its glycosylation. This is true for many mammalian proteins, especially cell-surface proteins.

Re: Doctors investigate mystery brain disease in Canada

#277

Post by eganp »

omgwtfbbq wrote: post #234
dnautics wrote: post #212

> CJD test came back negative So a CJD test is usually staining a biopsy with congo red and observing apple-green birefringence in the image. This generally works to detect amyloid plaques, which is common to all prions. So unless there was a lab mistake, the prion is localized elsewhere from where the biopsies are being done (FFI, for example, localizes to a different part of the brain) or they were using some other…

Are there other tests to determine prion disease related brain degeneration? Seems hard to believe they can't identify at all what the cause is.

Intracranial inoculation of infected tissue is the old-school way to assay for prion activity. Sometimes it takes a few years to get an answer though, especially in cross-species assays [0].

[0] https://link.springer.com/chapter/10.1007/978-1-4614-5338-3_...

Re: Doctors investigate mystery brain disease in Canada

#278

Post by petre »

giantg2 wrote: post #74
petre wrote: post #38

Earlier quoted context omitted.

Yes they do, unfortunately. And there are recently discovered cases of chronic wasting disease (CWD) in elk, deer and moose worldwide. I hope it doesn't pass to humans. For the time being I'll refrain from eating game.

I would be more worried about beef. There has been no evidence of CWD jumping to humans, but there has been for BSE. Also, do you have a link for the distribution? My understanding is that it is spread over a large geographic area, but that it's found in smaller clumps.

There are several maps and studies, depending on which country you're interested in. The best one that I've found was for Norway. Needless to say, it's spreading over an increasingly larger area every year.

Yes, BSE is also worrying, but beef that you buy at supermarkets is also checked more thoroughly compared to game meat. I'd worry more about restaurants and their suppliers.

Re: Doctors investigate mystery brain disease in Canada

#279

Post by JPLeRouzic »

fareesh wrote: post #157

I lived in Fredericton for about 7 years and have been around the province a bit. The air in Moncton is definitely unusual. I wouldn't be surprised if it has something to do with it.

Could it be the smell of cyanobacteria[1], gathered by tidal bore from the Petitcodiac river[2], specifically by Hall's creek reservoir[3]?

"This reservoir has experienced cyanobacteria algal blooms for many years due to high levels of nutrients combined with a lack of water velocity from damming."

[1] https://toxics.usgs.gov/highlights/algal_toxins/algal_faq.ht...

[2] https://en.wikipedia.org/wiki/Moncton#Tidal_bore

[3] http://www.petitcodiacwatershed.org/?page_id=302&lang=en

Re: Doctors investigate mystery brain disease in Canada

#280

Post by robbiep »

eganp wrote: post #276
robbiep wrote: post #167

Earlier quoted context omitted.

A nightmare scenario for me is the creation of mRNA coding for a misfolded PRNP being weaponised.

This probably isn't possible as the folding of PrP is not encoded in the mRNA of PRNP. The fold of PrP is a post-translational phenomenon, much like its glycosylation. This is true for many mammalian proteins, especially cell-surface proteins.

I’m aware of that. However the specific choice of amino acids can heavily influence the propensity to fold in a particular way. For example homozygotes for M129 have a much faster rate of vCJD development. Since Prion Diseases occur sporadically, the rate of mis folding can be increased and it probably wouldn’t be that difficult (even computationally) to determine how you can get it to misfold at a much higher rate.

I’m not sure what you mean by the fold being post translational, all folding is post translational, it’s literally the protein curling up into the lowest energy conformation as soon as it encounters the cellular environment, with assistance from HSPs if necessary. Unless you meant something else?

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