Human origin of Mad Cow disease?

This report in Nature was rather disturbing;

Human remains in cattle feed could have caused the first case of mad cow disease, two UK researchers propose. The hypothesis seeks to answer lingering questions about the fatal infection, which has affected 180,000 cows in Britain alone since the mid-1980s, and has gone on to cause more than 100 deaths in humans.

I don't know if I find the idea of cows passing such horrible diseases onto humans so easily more disturbing than the fact the cows may have ate human remains to begin with. So much for being vegetarians I guess.