Global Warning | 3 January 2009

Reading an account by the historian John Waller of the Dancing Plague in Alsace in 1518 recently, I could not help but notice the interesting but perhaps incomplete parallels with our own time.

Economic conditions in Strasbourg were dire in 1518 when a woman called Frau Troffea started dancing in public and continued for days on end until she was exhausted and had damaged her feet severely. Several hundred people soon joined her; the madness was collective.

What accounted for this collective madness? Some have suggested that it was caused by ergotism, a condition brought about by an ergot-producing fungus that spreads on mouldy grain; but, while ergot does cause visual hallucinations that send people mad, and a burning sensation in the extremities that might make them hop about for a while, the gangrene of the fingers and toes that is a prominent symptom of ergotism was never described among the sufferers of the dancing plague.