I read a story where a vamp lost his teeth and it had to be put back in place before sunrise and he died, never to regain his teeth. It was a romance novel.

There was also a story by Chris Pike that I read as a teenage. The main character converted a boy she cared for (she being very old) who had AIDS. In that story, the AIDS was "cured" because of the full blood transfer as she turned him.

I'm of the opinion that death and disease don't really matter to dead things. At the base of it, vampires are just zombies, who are aware and not decomposing. Presumably, if they are magic-based, the magic that sustains them and requires life via blood, would also heal disease such as that. Of course, it means you have to die first.

Science-based vampires really haven't tackled it, but most of those principles are seemingly based on magic anyway.