Vampirologist

A vampire is a being from folklore that subsists by feeding on the life essence (generally in the form of blood) of the living. In European folklore, vampires were undead beings that often visited loved ones and caused mischief or deaths in the neighbourhoods they inhabited when they were alive. They wore shrouds and were often described as bloated and of ruddy or dark countenance, markedly different from today's gaunt, pale vampire which dates from the early 19th century.

Vampiric entities have been recorded in most cultures; the term vampire, previously an arcane subject, was popularised in the West in the early 19th century, after an influx of vampire superstition into Western Europe from areas where vampire legends were frequent, such as the Balkans and Eastern Europe; local variants were also known by different names, such as shtriga in Albania, vrykolakas in Greece and strigoi in Romania. This increased level of vampire superstition in Europe led to mass hysteria and in some cases resulted in corpses being staked and people being accused of vampirism.

In modern times, the vampire is generally held to be a fictitious entity, although belief in similar vampiric creatures such as the chupacabra still persists in some cultures. Early folk belief in vampires has sometimes been ascribed to the ignorance of the body's process of decomposition after death and how people in pre-industrial societies tried to rationalise this, creating the figure of the vampire to explain the mysteries of death. Porphyria was also linked with legends of vampirism in 1985 and received much media exposure, but has since been largely discredited.

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Wikipedia