London, 1485. You wake in the middle of the night, feeling a bit apprehensive. The room feels so cold that you start to shiver, but it does you no good. Suddenly you are exhausted and fall back asleep. You wake again several hours later, too hot and sweating uncontrollably, mostly delirious. Ask any doctor of the time and he’ll confirm your worst nightmare: you have the deadly sweating sickness.

Sudor anglicus, the sickness that scared the English so much that any mention of it would cause an exodus of all those who could afford the move. Although it is not as well-known today as the black death, which killed far more people, sweating sickness made a name for itself at the time because it was usually fatal within 24 hours. However, here’s the rub: for once in Tudor England this was a disease you were more likely to get if you were rich rather than poor. In particular, upper class, middle-aged men suffered the worst (presumably why it was so well documented).

Never heard of it? There’s no need to panic the next time you feel a bit fluey. The sweating sickness hasn’t been seen since 1578, when the disease seemed to disappear just as suddenly as it arrived. It swept through England on at least five occasions, killing thousands,  arguably including the young Arthur, Prince of Wales (elder brother to Henry VIII), among other nobles. On one of its last sojourns through England it also spread to mainland Europe. It wiped its way through many countries as it spread eastwards, lasting at most two weeks in each place. The last major outbreak occurred in 1551 and all records of it end shortly thereafter.

Epidemiologically speaking, sweating sickness is a real head scratcher. The Sweat, as it was sometimes known, didn’t follow usual patterns of transmission and simply appeared at random in different locations. Its irregular pattern meant that, though it arrived during summer, there were often decades in between outbreaks¹. It seems as if we were safe up here in Scotland too, as the disease tended to stop at Scottish and Welsh borders, adding yet another mystery to the list.

Much like the black death and other historic diseases, you might think we’d have the cause for sweating sickness pinned down by now. Many diseases have been proffered by way of explanation, including influenza, scarlet fever, anthrax, typhus or hantavirus². However, none so far seem to fit the bill exactly when we consider the symptoms. For example, hantaviruses would not cause sweating and anthrax rarely ever passes from person-to-person. Of course, classifying a disease from a handful of historic reports is a difficult business. Some investigators have noted that if it were spread by animals, like rats, this might likely explain the wealthy targets. In those days, wealthier people tended to live in houses, which were attractive shelters for rodents.

We have many things to be thankful for in the 21^st century, not least our improved hygiene, vaccines and knowledge of infectious disease agents. Many such afflictions of the Tudor and other ages now have known causes and cures through the wonders of modern medicine. However, we should keep one eye on the past. Some of these more unusual illnesses may have disappeared, but we are still plagued by their relatives many centuries on. As for sweating sickness, the mystery continues…

Edited by Sarah Spence

1. There is speculation that this could be due to environmental or ecological factors, and a good overview can be found here http://www.historytoday.com/jared-bernard/dreaded-sweat-other-medieval-epidemic
2. If you would like to read more on this, medical researchers-turned-historians lead by Paul Heyman investigate further here http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3917436/