Hand of Vecna said:wel, remember, in the folk tales, Vampires were'nt just draining blood, they were draining life-force itself, using blood as a medium. Victims can regain their blood cells, but their life-force is still lost (and would be until major magical mojo is used to restore it).
In most folk tales, vampires didnt even have fangs; they had to use tools to open peoples' blood vessels. And in most folk tales, people didnt survive the vampire's attacks either, so it's hard to tell whatever they were restored after the vampire's bite or not ^^