How much do we know about the presence of prion diseases in other animals we frequently consume?
A quick search shows that even fish have some variant of the prion protein and so perhaps all vertebrates pose a theoretical risk of being the carrier of a prion disease, although the species barrier will likely be too high for prions of non-mammal origin.
I’m quite concerned about pigs.
Apparently pigs are considered to be prion resistant as no naturally occurring prion diseases among pigs have been identified, but it is possible to infect them with some prion strains under laboratory conditions.
A prion disease in pigs could be very bad for two reasons:
1: Pigs are often fed with leftover food from human consumption, this can become a potent vector of prion diseases between pigs.
2: Pork brain, spine, tongue, etc are frequently consumed in some parts of the world, this would make some humans exposed to a large amount of prion protein, if such an illness spreads between pigs.
Fortunately, nothing of this sort happened with pigs yet, and we have been consuming pork brain (and feeding pigs with leftover food) for centuries without known issues (but I doubt pre-modern people would’ve noticed the pattern, since the incubation period can be very long) so maybe pigs are resistant (enough) to prions that pork is very safe.
I was thinking of iatrogenic transmissions, yeah (and prions have been a long term psychological fear of mine, too...so I perhaps crawled too much publicly available information about prions to be a normal person)
I wonder if there are any instances of FFI transmitted through the iatrogenic pathway, and whether it is possible to be distinguished from the typical CJD, and whether iatrogenic prions could become a significant issue for healthcare (more instances of prion diseases due to aging population could possibly mean more contaminated medical equipments, and the possible popularisation of brain-computer interface might give us some problems too) given the difficulty of sterilising prions.
Maybe the sample size is too small for us to know.