Vampires have never been just a legend. They're just never thought of as real. Every one has seen at least one, but yet they are still seen as myth. Stories told to little to children, to keep them out of the woods.
But soon the vampires grew tired of being the stories around the camp fire. They want to be the bane of our existence. The reason we check under the bed and in our closet before we drift to sleep. This is what they want to be. They are just waiting until time.