Traditional Vampirism

[Campbell, Anne-TMC-Rcvg]

No: HPFGUIDX 88688

{Pippin}

Stoker is in the public domain and Rowling has already 
borrowed from him, at least I believe he is the one who 
integrated bats into the vampire legend. The vampire bat, though 
of course named for the monster, is a South American animal 
and was not part of European legends.

{Anne}
Has she? Other then describing Snape as 'batlike' (which does not automatically translate into "Snape is a vampire", no matter how tempting it is to say so. You may as well apply a Shamanistic viewpoint to that description and say his main animal totem is a bat, since he displays bat-like attributes--and since Shaman are a type of 'wizard', it would be as likely an explanation...), I don't recall her ever mentioning that particular ability...then again, I don't have the books with me. I'll be glad to see the passage quoted that states that though.
And as for Bram borrowing bats....I think that Vlad turned himself into a bat-like creature while at the castle with Harker, in order to spy on his guest from unique places, but don't recall him actually going completely 'batty' (if you will pardon the pun). Again, an actual passage clip would be appreciated, since my copy of Dracula was one of the things absconded by my former BF...

{Pippin}

As for the traditional vampire as sexual predator, Trachtenberg's "Jewish Magic and Superstition" gives this as a belief of Eastern European Jews, so perhaps the experts disagree. 

{Anne}
Entirely possible, I can concede that without pain *winks*. Mythology is full of contradictions when it comes to the 'experts' hashing it out. Greek mythology alone has so many contradictions by now that it's often impossible to tell what the 'original' version of any one myth was. 
However, back to my point about what vampire influences are most predominant now, Bram was not using the Jewish myths to refer to--he was referring to Slavic ones (influenced heavily by Christian, not Jewish beliefs), which had a much different view of vampires and their roles in the great scheme of things.
Also, as far as I knew, the Jewish actually had "Succubi" and "Incubi"--which are demons that prey on the sexual dreams of their victims. Although they could be easily identified as 'Vampires" by modern interpretations, they were considered a completely different entity--and demonic, not cursed humans--way back when folklore was not contaminated by the alterations of writers and movie scripters....