Kuru
I've got this fascination, and I think I have mentioned it before, with prion diseases, particularly Kuru. It's a progressive disease of the central nervous system marked by increasing lack of coordination and advancing to paralysis and death within a year of the appearance of symptoms. Thought to have been transmitted by cannibalistic consumption of diseased brain tissue - during ritual mortuary cannibalism - since the disease virtually disappeared when cannibalism was abandoned. Kuru is also apparently a fractional unit of money used in places like Egypt, Sudan, Lebanon, and Syria. Money is a brain disease. I can't argue with that one.