comment: >
  
  Prions are extremely resilient... I doubt composting would touch them.
  They even survive basic incineration which was basically unheard of in the pathogen world. 
  Not many things totally freak me out, but prions are one of my actual nightmares.
context: The issue back when this was killing people in the 80s was they were feeding the cows their own byproducts, like brains. That was causing it to spread so I assume this practice has stopped. >
  
  Prions are the cause of mad cow disease, and they are very difficult to destroy. Obviously feeding bovine by-products to cows is a concern, but fertilizing with manure from infected cows that hasn't been properly composted is a huge concern. We see e-coli outbreaks in lettuce from insufficiently composted manure. The spread of mad cow could happen just as easily. >
  
  Are you saying it because you know for sure (from actual studies) or are you just extrapolating from the e-coli stuff.
  Because one thing is a whole bacteria which has an actual cell wall that lets it resist the active chemical and biological agents of the outside environment, a completelly different thing is a random protein from inside an animal that's misfolded.
  I don't thing you can just presume that a protein will last long outside: it might, it might not.
  PS: Not a biologist, might be completelly wrong, would love to hear more about this.