Dancing Plague, Strasbourg, Alsace. 1518 (engraving)

The Dancing Plague of 1518 was a case of dancing mania that occurred in Strasbourg, Alsace in July 1518. Around 400 people took to dancing for days without rest, and, over the period of about one month, some of those affected died of heart attack, stroke, or exhaustion. Although the cause is still unknown, theories include food-poisoning caused by the toxic and psychoactive chemical products of ergot fungi, which grows commonly on grains in the wheat family (such as rye). Ergotamine is the main psychoactive product of ergot fungi, it is structurally related to the recreational drug lysergic acid diethylamide (LSD-25), and is the substance from which LSD-25 was originally synthesized;