10. Dance Fever
Those measures backfired, and simply ended up encouraging even more people to join the dance craze. Within a month, the number of nonstop dancers had ballooned into the hundreds, and at the height of the dance fever, 15 residents were dying each day from exhaustion and heart attacks.
The Strasbourg death dance was not an isolated incident. Between the fourteenth and seventeenth centuries, there were enough similar outbreaks for contemporaries to coin a term for the phenomena: Saint Vitus’ Dance, or Saint John’s Dance. There is no modern consensus on the cause, so it is simply categorized as an unusual social phenomenon – a mass public hysteria, or a mass psychogenic illness of unknown provenance.