Olivia: Born in 1756, Wolfgang Amadeus Mozart quickly became one of the most famous composers in the world. At the age of seven, he was already on tour, playing for aristocrats across Europe. By 1791, Mozart was 35, and he had a long list of masterpieces to his name – over 600 of them. But on December 5th, all of that was cut short. Just two months shy of his 36th birthday, Mozart died.

Even back then, that was pretty young. So what killed Mozart? The question has puzzled experts for two centuries, leading to more than 100 different theories, from murder plots to under-cooked pork chops to a simple vitamin D deficiency. Most of what we know about Mozart’s death comes from friends or family members – sometimes decades later – and the stories usually conflict.

The basic tale is that Mozart was sick in bed for 15 days, suffering variously from a high fever, rash, profuse sweating, severe swelling, pain in his limbs and back, nausea, vomiting, and diarrhea... until he slumped into a coma and died.

Mozart’s sister-in-law even claimed he said he could taste death in his mouth, but no one did an autopsy. At the time of his death, Mozart’s physician claimed that he died from miliary fever. But miliary fever was just a catch-all term for any infectious disease that came with a fever and a rash.

The suddenness of Mozart’s death was suspicious enough that within a week, a Berlin newspaper was circulating ideas about poisoning. There were even rumors that a fellow composer, Antonio Salieri, actually confessed to poisoning him. But the two go-to 18th century poisons, arsenic and mercury, don’t totally line up with the evidence.

If it was arsenic, that would explain Mozart’s nausea, vomiting, diarrhea and eventual coma. But he would have also experienced other symptoms, like throat burning or difficulty breathing, that weren’t reported at all. And mercury wasn’t necessarily a murder weapon, since it was sometimes used to treat syphilis at the time. It normally caused memory loss, tremors, irritability, and excessive salivation, and there were no report of those things. So, poisoning – as dramatic as that would be – is out. Sorry, conspiracy theorists.

One of the more striking symptoms of Mozart’s mystery illness was the extreme swelling. By some accounts, he was so puffed up that he could barely move. This points to some kind of kidney problem.

Kidneys filter your blood, getting rid of waste and extra fluid in the form of urine. But if your kidneys aren’t working well, that fluid can end up in tissues and cause swelling – also known as edema. Plus, that buildup of bodily waste can lead to vomiting, diarrhea, and even a metallic taste – which might have been that “taste of death” in his mouth. Usually, though, it takes a while for the kidneys to stop working. And Mozart’s death was quick.

Other theories suggest that Mozart’s killer was some sort of infectious disease, like rheumatic fever. Rheumatic fever is a disease that’s caused by a really bad streptococcus bacterial infection, like untreated strep throat. Eventually, your immune system mistakenly attacks your own body, including your joints and your heart. And the symptoms line up pretty closely: it explains Mozart’s swelling, his rash, and his high fever.

But this disease usually only kills people after severely damaging their hearts, and Mozart didn’t seem to have heart problems. So even with these promising theories, Mozart’s death was still a mystery.

In 2009, a group of researchers decided to dig into Vienna’s daily death records for more clues. They found that around the time Mozart died, there was a spike in the number of young men in the city who had similar symptoms, like edema, and died too – like a small epidemic. With all this additional data, the researchers proposed that Mozart died from some sort of streptococcal infection. But instead of death by rheumatic fever, the infection may have led to a severe kidney problem, which caused all that swelling.

Of course, there’s no way to know for sure if they’re right. But the study is impressive detective work, and their theory seems plausible. Either way, as we learn more about medicine, more theories might come up. And everybody loves a good mystery!

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