Vampirism n. : Belief in the existence of vampires.

Vampirism n. : The actions of a vampire; the practice of bloodsucking.

Vampirism n. : Fig.: The practice of extortion.

Example:
I need some good websites on the facts of vampires and Vampirism?

Taxonomy
vampire, Death, blood, Burial, belief, corpse, body, vampiric, Chinese vampires, modern vampires, London, vampirism, folkloric, soul, Dracula, spirits, folklore, legends.

Defination from the web:
vampirism. ... Porphyria was also linked with legends of vampirism in the 20th century and received much media exposure, ...