So what's a description of a zombie,basically a mindless drone,urged by the desire to feed.Of course according to folklore a zombie is a walking cadaver, although vampires are also walking cadavers,both working on the same principle: in order to assure their own survival they need to feast on the living.
But why would a dead body need to survive.Now that's the paradox.Vampires,zombies,mummies, if they're all dead, why do they want to live so bad,even if they are the "living dead" they are still dead.
Scary? Well not really,it's just another form of parasitism,except this time it affects the nervous system and thus the behavior. It's just biochemistry at it's finest. If this would happen to humans it would be a lot less scarier than the diseases and illnesses we have today.Why? Because we can probably kill it.