England’s Sweating Sickness
In 1485, a previously unknown ailment appeared in England. The onset was very quick and started with cold shivers. This was followed within a few hours by an increase in body heat and copious sweating. There were headaches, aching joints and limbs, elevated pulse rate, delirium, and pain in the heart.
The sufferer collapsed into a state of total exhaustion and “its victims were killed within 24 hours by sweating to death” (History Today). One chronicler noted an even shorter span with those infected being merry at dinner and dead by supper. Usually, people fell into a deep sleep from which they never awoke. The mortality rates were between 30 percent and 50 percent.

Doctors Were Baffled
In its first incarnations, sweating sickness was largely confined geographically to England and it turned up every few years in the summer. Doctors struggled to explain what caused it and had only a limited arsenal of treatments.
Medieval medicine blamed most illnesses on demons or a bad alignment of the stars. In others cases, patients were believed to bring sickness upon themselves through their own sinful behaviour. And, of course, the ever-popular blaming it on witches could be called upon as an explanation for the inexplicable.
Therapy involved a lot of bleeding, purging, and induced vomiting. Trepanning, that is cutting a hole in the skull, was a useful way of evicting the bad humours from the brain. Or, there was self-flagellation with knotted ropes as a way of earning God’s approval so that he would bring about a cure.
Predictably, none of these treatments worked once an epidemic took hold.
Not for the Faint of Heart
More Outbreaks
There are no historical records of sweating sickness following the first cases in 1485 until 1502. There was another in 1507 before a big one in 1517.
The last mentioned hit Cambridge and Oxford as well as other cities where it claimed about half the population. This eruption crossed the English Channel and appeared in Calais, France.
In 1528, it ravaged the English capital and Henry VIII was so alarmed by the spread of the disease that he escaped to the countryside. At the time, the king was wooing Anne Boleyn. She became a victim of sweating sickness but, fortunately, she recovered. Or, it’s arguable how fortunate in that she married Henry, fell out of favour, and had her head lopped off in 1536.
The malady suddenly popped up in Hamburg and spread along the Baltic coast to reach Poland, Lithuania, and Russia. The Scandinavian countries were also afflicted.
The last major epidemic was in 1551. As with most of those before, it started in London and then spread throughout the country. Curiously, it never crossed the border into Scotland.
After the 1551 rampage the curious ailment vanished. Speculation is that the virus mutated into something less lethal.

The Work of John Kays
Educated at Cambridge University John Kays took up the medical profession and Latinized his name to Johannus Caius. It was the fashionable thing to do at the time.
He had a close-up view of the sweating sickness eruption of 1551. He studied how it affected its victims and delivered his verdict in his 1552 book, A Boke or Counseill Against the Disease Commonly Called the Sweate or Sweatyng Sicknesse.

The illness appeared to hit rich people more than the poor; the young and healthy were also more likely to succumb. Dr. Caius attributed its cause to the dirty and filthy conditions in which most people lived.
As many of his patients were wealthy, the good doctor was able to make a lot of money. This despite the fact that any treatment he delivered made not the slightest difference to the progression of the sweating sickness.
He made so much coin that he was able to richly endow his old Cambridge college, which changed its name in gratitude to Caius (pronounced keys). It continues to operate under that name today.
What Was the Sweating Sickness?
A cottage industry has developed among medical detectives who have tried to figure out exactly what it was.
Various theories have been put forward: scarlet fever, influenza, plague, severe acute respiratory syndrome (SARS), anthrax, botulism, and others. Although curiously, nobody has suggested a virus hitchhiked on a meteorite – yet.
But none of the suggested ailments quite fit the known symptoms.
Now, researchers have settled on some form of hantavirus as the villain. They came to this conclusion after an outbreak of a similar sickness among Navajo people in the American southwest in 1993.
The Independent reports that the cause of the illness among the Navajo was “… the Sin Nombre virus, a member of a group of viruses mostly known for causing kidney failure syndrome, and a cousin of several tropical fever viruses transmitted by biting insects. The new disease was given the name hantavirus pulmonary syndrome (HPS).”
The virus is carried in the droppings of deer mice and other rodents. When the droppings are swept away by a broom, the virus becomes airborne and can be inhaled. Or, people working in fields might unknowingly come into physical contact with rodent droppings.

HPS, although rare, is still with us. It has popped up in slightly mutated form in Florida and New York.
And, the Centers for Disease Control adds that “More recently, cases of HPS stemming from related hantaviruses have been documented in Argentina, Brazil, Canada, Chile, Paraguay, and Uruguay, making HPS a pan-hemispheric disease.”

Bonus Factoids
According to WebMD “About four out of 10 people who get HPS do not survive.”
After the 1551 epidemic, the English Sweating Sickness vanished, until a similar ailment struck in Picardy, northern France in 1718. In 2014, A group of medical investigators suggested a similar hantavirus may have been the cause of both infections. There were several other occurrences of the Picardy Sweat until it too faded away in 1918.
Sources
- “The Dreaded Sweat: the Other Medieval Epidemic.” Jared Bernard, History Today, May 15, 2014.
- “Medicine in the Middle Ages.” BBC Bitesize, undated.
- “What Was the ‘Sweating Sickness’ in ‘Wolf Hall’? ” Derek Gatherer, The Independent, February 10, 2015.
- “Were the English Sweating Sickness and the Picardy Sweat Caused by Hantaviruses?” Paul Heyman, et al., Viruses, January 2014.
- “The Sweating Sickness Returns.” Discover Magazine, June 1, 1997.
- “Hantavirus Pulmonary Syndrome (HPS) - Topic Overview.” WebMD, undated.
- “Tracking a Mystery Disease: The Detailed Story of Hantavirus Pulmonary Syndrome (HPS).” Centers for Disease Control, August 29, 2012.
Questions & Answers
Comments
Very sad and interesting. A lover of history will love your Hubs. Thanks for sharing with us.
That's a good point, actually. If the latest was the hantavirus in 1993, it's still around. I lived for a while in NM, and the hantavirus was considered serious stuff. I was there from 1993 until 2006 and I still considered it when I cleaned.
S0, yes, I guess it has not died out.
This is a very interesting article on sweating sickness. I do not remember learning about this one in nursing school. It must be fun to study diseases that have died out.
I've never heard of sweating sickness before. Thanks for sharing the information. It's very interesting.
Such an interesting post - and I love the title! What a hard time to live, well one dead, dead by morning.
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