Dancing plague of 1518
The outbreak began in July 1518 when a woman called Frau Troffea began to dance fervently and uncontrollably in a street in Strasbourg. According to Ned Pennant-Rea, "Frau Troffea had started dancing on July 14th on the narrow cobbled street outside her half-timbered home. As far as we can tell she had no musical accompaniment but simply 'began to dance' ... some of those who had witnessed her strange performance had begun to mimic her, and within days more than thirty choreomaniacs were in motion, some so monomaniacally that only death would have the power to intervene." Troffea kept up the constant dancing for a week. Soon, three dozen others joined in. This is known and believed by some to be a perfect example of a nocebo effect which can make some feel ill simply by being under the expectation of being ill. By August, the "dancing plague" had claimed 400 victims. Dancers were beginning to collapse. It is said some even died from a stroke or heart attack. The victims' movements were described as spasmatic with many convulsions and their bodies were left drenched in sweat. Their arms would thrash violently and some noted that their eyes were vacant and expressionless. Blood would pool into their swollen feet and they would eventually bleed into their shoes. Often, there would also be cries for help from the affected. If the victims did not succumb to a heart attack, they would collapse from extreme exhaustion, hunger, and thirst. There were as many as 15 deaths per day during the outbreak’s peak, but the final number of fatalities is unknown today. No one knew what caused this reaction, which meant no one understood how to remedy it. By early September, the outbreak began to subside
