When considering the reality of vampires and questioning their existence one should first consider this:

There is a form of clinical vampirism called Renfield's Syndrome where the sufferer feels uncontrollably compelled to drink blood. The Syndrome afflicts mostly males. There are three stages to the disorder:

First is autovampirism or autohemophagia where the sufferer drinks his own blood. The second is when the disorder compels the afflicted to drink animal blood by eating live animals and drinking the life giving liquid. The third and final stage is when the individual suffers from true vampirism and begins to drink human blood, not his own. This is usually accomplished from stealing from blood banks, hospitals and sometimes straight from the source. . .a living human. As can be imagined, this condidition can sometimes lead to murder or other crimes against man.

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