https://www.ncbi.nlm.nih.gov/pubmed/28159831 https://www.ncbi.nlm.nih.gov/pubmed/28159831 Yes, and that's not mutually exclusive with there being a biochemical

https://www.ncbi.nlm.nih.gov/pubmed/28159831 https://www.ncbi.nlm.nih.gov/pubmed/28159831 Yes, and that's not mutually exclusive with there being a biochemical risk factor that triggers it or increases susceptibility. It is certainly a little out there, but if I had to guess at some hidden danger that's ubiquitous in our environment to which we are oblivious, I'd say "prions are more prevalent and dangerous than we think" isn't a bad place to start.