I am fascinated by all things relating to the vampire phenomenon. Except TWLIGHT. (Weekly mandatory dig at Stephenie Meyer’s travesty, fait accompli!) I have studied extensively the real-life factors that may have/probably did facilitate the spread of the belief in vampires, all the stock answers: illness, premature burials, a lack of understanding of the decomposition process. I can quote from the documented cases of authentic vampire disinterment. (Authentic in the sense that bodies were really dug up and staked, burned, decapitated, etc. and those bodies were believed to belong to vampires.) I know the origin of the use of garlic to repel revenants and the like.
The thing that really fascinates me, though, is that there are places in the world right now TODAY where vampires are still real. Believed to be real, at least. In 2004, in Romania—where else?—a young woman grew sick, reporting that a dead relative was attacking her during the night and drinking her blood. The accused was dug up and staked. In 2004. Vampires are still with us. Thank goodness.