I have long suspected that the human prion disease (Creutzfeldt-Jakob) and the varieties found in at least some other mammals are related. It is strongly suspected that so-called variant CJD (vCJD) is what happens to a human who contracts the agent of bovine spongiform encephalopathy (BSE, or mad cow disease). Now, “two cows have been discovered with a form of BSE that looks very different from the usual kind, Italian scientists have reported.

It resembles one form of the human prion disease, sporadic CJD, raising the possibility that this human disease is acquired from cattle.” —New Scientist