tarantism

n. disorder characterized by an unnatural desire to dance and thought to be caused by a tarantula's bite (prevalent in Italy during the 15th and 17th centuries)

Tarantism is, allegedly, a deadly envenomation resulting from the bite of a kind of wolf spider called a "tarantula" (Lycosa tarentula). (These spiders are different from the broad class of spiders called "bird eating spiders" or "Tarantulas".) The condition was common in southern Italy during the sixteenth and seventeenth centuries. There were strong suggestions that there is no organic cause for the heightened excitability and restlessness that gripped the victims. The stated belief of the time was that victims needed to engage in frenzied dancing to prevent death from tarantism. Supposedly a particular kind of dance, called the Tarantella, evolved from this therapy. Many people have suggested that the whole business was a deceit to evade religious proscriptions against dancing.
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Noun
1. a nervous disorder characterized by an uncontrollable impulse to dance; popularly attributed to bite of the southern European tarantula or wolf spider
(hypernym) chorea

(n.)
A nervous affection producing melancholy, stupor, and an uncontrollable desire to dance. It was supposed to be produced by the bite of the tarantula, and considered to be incapable of cure except by protracted dancing to appropriate music.
  

an urge to overcome melancholy by dancing