There are many mythological beings that have touched base with vampiric or animalistic qualities. However these beings weren't common, they were actually very much the opposite.
In the astral you will find vampiric like beings but they are nothing like fictional movies and books claim. As for werewolves, unless its a shapeshifter, werewolves were a superstition built off of the ignorance of disease.
The werewolf hysteria surrounds what we call "lunacy" and "rabise". When a person develops rabies they go insane because their nervous system begins to shut down, they foam at the mouth, and act wild. If they bite someone (which is an instinctive reaction for all creatures) the person bitten would "turn" aka develop the disease themselves. Lunacy is even experienced today, there are more murders and violent crimes during full moons. And it is where we get the term "lunatic".
Vampires...well there are quite a lot of theories. I've mentioned some in another topic. But here is one I didn't mention. There is a disease that even exists today that prevents the body from absorbing iron. This is known as a form of anemia! This causes the person to turn very pale and deathly looking, frail. They will eventually die without treatment. Now when people have this problem they are given iron intervenously, by injection, or overdosing on iron pills. But then there was no such treatment. Drinking blood however gave the person a huge dose of iron, so some people did so. Not very healthy but the other alternative was death so really what did they have to lose?
Iron deficiency causes a sensitivity to light, so that is why vampires were thought to burn in the sun. It also causes cold hands and feet which gives the impression of someone being "dead"
So there you go. For all those who want to be a typical vampire so badly. All you are trying to portray are poor people who suffered from anemia when there was no treatment.