 instructor of medicine at the Department of Global Health and Social Medicine at Harvard Medical School, states that bovine spongiform encephalopathy or BSE is the first man-made epidemic, or "Frankenstein" disease, because a human decision to feed meat and bone meal to previously herbivorous cattle (as a source of protein) caused what was previously an animal pathogen to enter into the human food chain, and from there to begin causing humans to contract vCJD.As of 2018, evidence suggests that while there may be prions in the blood of individuals with vCJD, this is not the case in individuals with sporadic CJD.In 2004, a report showed that vCJD can be transmitted by blood transfusions.