[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.

[hajile]

The CDC disagrees with your assessment. Do you have any sources about this?

According to the CDC, CWD is spread NOT just through saliva, but also feces, blood, urine, etc.

In addition, it CAN spread to Squirrel monkeys. The long-term affects on macaques is still being established (on of the reasons kuru took so long to discover was that it took decades for the monkey to develop symptoms).

If exposure is dangerous to humans, what could we do? In the areas it has been in, it is spread everywhere the deer travel as they shed bodily fluids into the soil.

source -- https://www.cdc.gov/prions/cwd/transmission.html

[dnautics]

So I should have disclaimed that my information is as of 2009, which is the last time I touched this stuff, but that site said there was not successful transmission into monkeys in another experiment by the lab. I mean these experiments are extreme, high dose boluses of material straight into the brain. If at least one experiment failed to do that into monkeys that says something, even if they managed to get it in a later one, unless there was some revelation that they had done it wrong the first time.

[giantg2]

"there is not species crossover between deer and cow/sheep/humans"

I thought the theory was that CWD started in a domestic herd that was raised in an area that previously had scrapie infected sheep?

[dnautics]

These things can also happen autogenously (there is sporadic cjd) so who knows.

[danesparza]

Wait, wait, wait. Your advice seems contradictory: "there is not species crossover between deer and cow/sheep/humans"

and

"Incidentally, you probably shouldn't eat beef tongue."

Can you clarify?

[dnautics]

Sorry, the grouping was unclear.

There is not deer <-> sheep, deer <-> cow, deer <-> humans.

There is cow <-> sheep, maybe cow <-> human. I don't know off the top of my head about sheep <-> human

If there had been, the us food supply would be trashed. Cwd is highly endemic among wild deer and wild deer co-graze with cows all the time.

Also unknown if the relationship can be transitive. There might be a species X where deer <-> X <-> human.

[chasil]

Scrapie appears to have been the ultimate cause of a human CJD outbreak:

"...in 1996, with the recognition in young people in Britain of a “new variant” of Creutzfeldt-Jakob disease (nvCJD, or the Will-Ironside syndrome) that has since been traced with near certainty to the consumption of tissue from cattle infected with spongiform encephalopathy (BSE), they having in turn consumed meat and bone meal contaminated with rendered sheep carcasses infected with scrapie... There are currently just over 30 verified cases of nvCJD, and four to five new cases a year: whether they represent a small group of susceptible people or are the leading edge of a major epidemic is still moot."

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1114482/

[wil421]

No lengua tacos? What will I get now?

[dnautics]

Cabeza. Which is usually the cheek meat. Avoid sesos, of course.

[mgarfias]

But lenguas?!?