The question I received today: "How are vampires different from human beings, biologically speaking?"
The answer is simple and complex. Vampires do not subject themselves to experimentation, obviously, so the study of vampire physiology is limited. no hunter as of yet has ever been able to capture an active vampire to test it. Study of the dead creature, however, reveals signs of some form of cutaneous porphyria in the body. This alone, however, does not create a vampire. There is something else involved in the process, and science has not pinned down just yet what it is.