Vampires - Could they be real?

I recently wrote an article speculating on whether Zombies could be real now, or at some point in our future.  And while the evidence might be a little shaky it does show that, given the right circumstances it is possible.

So that got me thinking of what other "mythological" creatures could be real.

I figured, since vampires seem to be all the rage today, I thought I'd look into that.

If you do some digging, you find that Vampires go back hundreds of years.  Not only that, but there are legends speaking of blood sucking creatures spanning many continents and in many countries.

This makes me wonder, then, if there is or was some truth to the vampire legend.  Did vampires actually exist at some point? And if so, do they still exist?

Now for some of the theory behind vampirism:

According to a few sources, there are ways which a person could contract something similar to vampirism.  Whether it is from something as common as Rabies, or something more unique called Porphyria, a rare blood disorder.

According to a Spanish Neurologist, Dr Juan Gómez-Alonso, there is a link (however tenuous) showing that some of the side effects of rabies are remarkably similar to what we'd consider to be a vampire.  From susceptibility to garlic and light, to a preference for a nocturnal lifestyle to hypersexuality.  These are all traits known to be associated with vampires.

The link to Porphyria was something which was apparently proposed in 1985 by biochemist David Dolphin, however it was debunked by most of the scientific community.

That's not to say he couldn't be on to something, just that others don't agree.  He surmised that vampires were merely sufferers of porphyria seeking to replace haem (a form of iron in the blood), and that's why they drank large amounts of blood.

That doesn't explain the other facts we know about vampires, however some of those are addressed by the Rabies hypothesis.

So, knowing that, if someone suffered from Porphyria AND rabies, wouldn't they then have most of the classic indicators of vampirism?

If these 2 conditions could co-exist wouldn't that then mean that someone could be considered a vampire?