Atlas Obscura on the origins of vampires and their relationship with spreading diseases:
In many respects, the vampire of today is far removed from its roots in Eastern European folklore. As a professor of Slavic studies who has taught a course on vampires called “Dracula” for more than a decade, I’m always fascinated by the vampire’s popularity, considering its origins—as a demonic creature strongly associated with disease.
The first known reference to vampires appeared in written form in Old Russian in 1047, soon after Orthodox Christianity moved into Eastern Europe. The term for vampire was upir, which has uncertain origins, but its possible literal meaning was “the thing at the feast or sacrifice,” referring to a potentially dangerous spiritual entity that people believed could appear at rituals for the dead. It was a euphemism used to avoid speaking the creature’s name—and unfortunately, historians may never learn its real name, or even when beliefs about it surfaced.
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Scholars have put forth several theories about various diseases’ connections to vampires. It is likely that no one disease provides a simple, “pure” origin for vampire myths, since beliefs about vampires changed over time. But two in particular show solid links. One is rabies, whose name comes from a Latin term for “madness.” It’s one of the oldest recognized diseases on the planet, transmissible from animals to humans, and primarily spread through biting—an obvious reference to a classic vampire trait.