In 1518, residents awoke to find piles of bodies littering the streets of Strasbourg, with every corpse showing signs of the same grim plague.
The victims, of which there were perhaps as many as 400, had not been struck down by the Black Death, nor any other illness known to doctors both then or now. Instead, these unlucky Strasbourgians had been killed by excessive and involuntary dancing, the cause of which has fascinated experts to this day.
But what was behind this baffling chapter in history, and could we be at risk of a similar plague striking in the modern day?
The Daily Star has been poring through our history books and dusting off our medical journals to get to the truth.
The First Dance
On a hot summer’s day in July, 1518, a woman by the name of Mrs Troffea stepped out into the street and began to dance.
No music nor cause for celebration prompted the outburst, and yet she clearly felt some inexplicable drive to stand amongst her neighbours and, in total silence, boogie like there was no tomorrow.
According to historical documents, Troffea’s silent shindig drew in a crowd of passers-by, including her husband, who stood to watch the bizarre but captivating spectacle.
They would not remain spectators for long, however. One by one, those in the crowd seemed to become afflicted by the same strange impulse, and within hours the streets of Strasbourg became full with frenzied dancing.
Contemporary accounts make clear that this wasn’t some restrained waltz being performed, but instead a manic, flinging of limbs that left sufferers drenched in sweat.
Dancers would apparently stop briefly to sleep once the exhaustion had totally overcome them, but as soon as they woke up the dance would start again.
Authorities step in
Unsurprisingly, Strasbourg’s leaders quickly grew concerned by what was happening in their streets, and emergency meetings prompted a surprising response.
Rather than try to crack down on the dancing, officials decided to organise specialised dancing events and galas, in the hopes that those afflicted could be sated of their seeming desire to dance themselves to death.
Some reports suggest that hundreds of tickets were sold and even that professional dancers were brought in to supervise.
Obviously, this did not work at all. Instead, the plague spread like wildfire, with hundreds more becoming afflicted by the unique condition.
Eventually, what started as a peculiar but seemingly light-hearted issue started becoming gravely serious, as one by one dancers started dropping dead from exhaustion and extreme muscular distortion.
It’s not known exactly how many people died from the plague, with one account suggesting the figure could have been as high as 15 dancers each day.
Thankfully, the plague did eventually stop in September, but only after two months of solid dance.
What caused it
Scientists and historians still debate exactly what caused the dancing plague, with most holding one of two opposing theories as to what was behind the urge.
One thought is that the dancing was caused by a mass, and accidental, hallucinogenic spiking, perhaps originating from a batch of rye bread containing the dangerous ergot fungus, which is known to cause convulsions and visions.
Ergot is known to grow in the area in and around Strasbourg, which lies on the French-German border, and has been found on batches of rye grain in recent decades.
Another theory, put forward by US medical historian John Waller, is that those afflicted by the plague were experiencing a form of mass psychosis, potentially triggered by extreme stress caused by things like the Black Death.
Could a dancing plague happen now?
In short, the answer is yes it absolutely could.
While rare, both incidents of mass psychosis and things like food chain contamination do take place in the 21st Century, and so if either were to be the cause of the dancing plague then in theory we could see a repeat.
There have been numerous examples of mass hysteria and mass psychosis in recent years, including an incident in 2011 that saw sufferers display similar symptoms to those present during the 2011 plague.
Between October 2011 and June 2012, twenty people in Le Roy, New York, mostly teenage girls, became afflicted by constant physical and vocal tic-like movements and speech difficulties, prompting experts to compare the two incidents.
For those who believe that the plague was not simply mass hysteria but instead ergot contamination, while food standards agencies do instil stringent measures to stop outbreaks, the fungus does very much does still exist.
According to a spokesperson for the UK’s Agriculture and Horticulture Development Board, farmers “know more about” the fungus and so can “have a much greater ability to manage” it.
AHDB Senior Cereal Product Quality Scientist Kristina Grenz said:
“We now know far more about ergot. By mitigating ergot risks in the field and in grain, combined with modern production practices, we have much greater ability to manage ergot than we did in the past.
“The ergot management interventions will need careful integration in production systems, especially to deal with competing objectives, such as the use of reduced tillage or ergot-susceptible grass species in field margins. The strengthened guidance will help farmers balance decisions in view of the risks and the opportunities.”
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