I have been doing a lot of reasearch in my spare time and I have found that there are different types of vampires, which are different from the folkloric vampires. I hope to write some information on the different types that there are, at least according to my understanding, and evaluate them as to the potential dangers and hazards that each type may pose.
There are a a lot of different types, ranging from people who just dress up and act like they are vampires, or play vampire roleplaying games; to those who have a blood fetish; to those who crave blood; to psychic vampires who don't even drink blood, but steal people's energy instead; to the predatorial types; to undead vampires; to people who are completely mental and think they are vampires.
OK, on my other page I have a whole long list of folkloric vampires from around the world and history, but here I am going to discuss modern vampires.
(This could take a while to write, so check back here soon, and I should have more information up. I wanted to get this much up so you'd know what to expect once I get the whole thing done.)
The first kind of "vampire" is the lifestylers, who call themselves "vampyres" with a Y to distinguish themselves from undead vampires. Most of these people are just people, and not vampires at all; they just enjoy the style and the culture of the vampires, so they immerse themselves into it and try to make it as real as they can. Some of them are vampires though, from what I've heard, and some of them are people who drink blood. Most of them are harmless because they enjoy dressing up like vampires, but dont actually go and DO anything to anyone.
There are blood fetishists, who are people who get off sexually from blood. They have a willing partner who donates, or likes being scratched or cut, and they generally don't take very much, probably a few drops -- just enough for the taste and the idea of it. I don't really think they are considered vampires, though. At least, not by the vampires.
There are sanguinarians, who are those who crave blood. Sanguinarians is what they call themselves; they are vampires, but they are human vampires. Generally speaking, they get their blood from people who are willing (donors or sources). Stuff like crosses and holy water doen't have any effect on them, and as far as I know, they are not undead. But they are not immortal, either.
Psychic vampires don't need blood. They take energy from people. Sometimes they drink blood, I think, but they claim they don't NEED it. Supposedly it's the energy in it. If you are around one, then you'll start to feel way tired if they are feeding off you. If that happens, then they will start to feel energized, and when they go away, then you'll start to feel better. It's hard to figure out if they attack people or not, because if they do it's not physical, so you don't see it happen. They sometimes feed on someone's energy during sex.
Sometimes, they don't even know they are a psychic vampire, and are not even realizing it if they are feeding off of someone; they just do it. But there are others who know it, and consciously choose to do it.
Immortal vampires. They are elusive and secretive, and I haven't been able to find out too much real information about them, because they aren't going to readily admit what they are. Too much at stake (ha-ha). From what I can tell, they are pretty powerful. Some of them are good, but some of them basically view us as food and tools. From what I gather, they HAVE to have blood or they'll die; so they aren't above getting it by force. They have altered DNA so they are different from humans. I would say that this type is the ones who pose the greatest threat to society.
These are the ones who are the predators. They are faster, stronger, probably smarter than a regular human. I don't think they can hypnotize their prey or anything like that, and I don't know if they kill to kill, or if they do it sometimes on accident. But these are the ones that you need to watch out for.
They are also the most likely ones to be rogues. They have to have blood to survive, and they will do whatever it takes to get it. Sometimes they can't handle being the way they are and they go nuts or go on a rampage.
Then there are people who are mental, who think they are vampires or are scizophrenic, who may go around and kill or attack other people. When the police finnaly round them up, they claim they did their crimes because they were vampires. Crazy people (poor bastards...)
I will eventually put up more information and links here, but this is the basics for now.