You can cure dead in TES (and therefore you can cure undead), there are many examples, like the witches that cure you from lycanthropy in Bloodmoon (btw: they are from the same coven that cure you from vampirism in Oblivion).
Since when can you "cure" dead? Or undead, for that matter? Rather, what do you mean by cure? It sounds like resurrection, which isn't curing. As for curing the divine curse Lycanthropy or Vampirism, sure, you can sure that. Because it's a disease. Not a state of being undead. You can't cure zombies or skeletons, liches, ghosts/wraiths. Maybe a disease on them, sure.
Yeh, but the girl had to be sacrificed during the ritual and than she was brought back to life.
And talking about "metabolic functions" in TES? You know, there are people here that will bite your head off for bringing real world science into TES.
Lol I know that all too well, as well. I've had them snap at me, but there are logical things within TES (aka some science at the root), like metabolic functions. =P
Thought it was a zombie, not a wormy. Could be wrong.
Aren't wormies just zombies created magically by ol' Manni?
I haven't noticed that vampires have to eat or drink. They can drown in water, but I would consider this game mechanics not lore.
They do need to consume a life force, for whatever reason. Since there are different types of vampires, it's hard to say why in a general sense. I think the Morrowind clans need to eat or "die". But don't hold me to that, and feel free to correct. But we could even take the case of Count Hassildor's wife, who didn't eat and was incredibly weak, or from what I remember. And while eating for Cyrodillic vampires may make them closer to human, and not eating makes them stronger, I would say it's actually a bad thing to not eat. Not eating seems to make them wild and feral, and I would suspect they'd obviously grow weaker/etc over time, making the strength side effect wear off.
They have to breath, they do eat but blood is primarily their food and drink. Also, the DB vampire does make a reference that he does consume food, but is highly allergic to garlic. I'm also sure that vampires still have to [censored] and urinate.
In the case of Cyrodillic vampires, maybe like Count Hassildor, he probably may eat infront of other nobles to keep up appearances. Speculation, but I think he does.
There is a difference between "they have to eat" and "they can eat".
I believe that consuming blood have different meaning for vampires than consuming food have for living creatures. It is common for undead beings to consume blood in real world mythology. I think it can be about stealing the life force that they miss.
Real world mythology? This is TES.
But we also have a non-mythological creature that requires blood -- the vampire bat. With that, we can hypothesis that Vampires in TES may be the same, which is more or less the same thing you are saying (stealing life force), but less on the life force and more on the nutrition of it, which again, to bring science and metabolic functions into it, would make since. Malnourished vampires grow weaker.