No, it is not a joke, it really happened and many times in Europe between the 14th and 17th centuries




THE DANCING PLAGUE OF 1518

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"The dancing plague (or dance epidemic) of 1518 was a case of dancing mania that occurred in Strasbourg, Alsace (now modern-day France), in the Holy Roman Empire in July 1518. Somewhere between 50 and 400 people took to dancing for days."

"The outbreak began in July 1518 when a woman began to dance fervently in a street in Strasbourg.[1]


Controversy exists over whether people ultimately danced to their deaths.

Some sources claim that, for a period, the plague killed around fifteen people per day;[2] however, the sources of the city of Strasbourg at the time of the events did not mention the number of deaths, or even if there were fatalities.

"Less than 50%"

DANCING MANIA IN FURT IN 1374

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"Further outbreaks occurred during the 13th century, including one in 1237 in which a large group of children travelled from Erfurt to Arnstadt (about 20 km (12 mi)), jumping and dancing all the way,[6]:201 in marked similarity to the legend of the Pied Piper of Hamelin, a legend that originated at around the same time.[8] Another incident, in 1278, involved about 200 people dancing on a bridge over the River Meuse resulting in its collapse. Many of the survivors were restored to full health at a nearby chapel dedicated to St. Vitus.[2]:134 The first major outbreak of the mania occurred between 1373 and 1374, with incidents reported in England, Germany and the Netherlands."

There were many others, the last was registered in Madagascar in 1863 but it s hard to find good informations.