My pet theory on CWD and other prion diseases is that it goes back to the 1700s with Scrapie, which is basically Mad Cow Disease or CWD in sheep.
I am fairly convinced that this is due to the introduction of mammalian protein/by product into the feed of sheep starting back into the 1700s.
Note, no sheep, cow, horse, deer, elk, etc. will EVER resort to cannibalism in order to survive during a starvation event. You could have a flock of
50 sheep in a pin and never feed them, and none of them will resort to cannibalism in order to survive. If a bunch of deer are starving in the winter,
they aren't going to start eating their buddies whenever they die due to starvation
As such, these types of animals will never resort to eating mammalian protein in order to survive.
These prion diseases only seem to have come about whenever humans started introducing mammalian proteins into their diet, which apparently began in the 1700s.
We then see the rise of prion disease in the form of Mad Cow Disease. Again, did it "jump" from sheep to bovine or was it because
of the feed being provided to bovine? Still unclear.
Regardless, the question now is, how did it jump from livestock (sheep, bovine, etc.) into deer?
Is it because farmers began putting out feed with mammalian protein in it for deer bait? Was it because the urine and feces of infected livestock got
into the watershed and deer became infected therefrom? Who knows... regardless, it's here. And the big worry is if it makes the jump into humans.