The Composer Who Couldn't Turn Over in Bed

What We Know

On September 30, 1791, Wolfgang Amadeus Mozart stood in the pit of a theater outside Vienna’s walls and conducted The Magic Flute’s first night. He was thirty-five. On November 18 he conducted one more piece in public, a short cantata for his Masonic lodge’s new temple, and two days later took to his bed. He did not get up again.

For the next two weeks his body swelled. His sister-in-law Sophie Haibel, who helped nurse him, later described a man so swollen he could no longer turn himself over, and a nightgown that she and his wife Constanze had to refit so it opened down the front, because he could no longer be dressed the ordinary way. He ran a high fever. Early in December he rallied enough to gather friends at his bedside and sing through parts of his unfinished Requiem, then relapsed. Just after midnight on December 5, 1791, he died at home, Constanze and Sophie beside him.

His physician, Thomas Franz Closset, and a second doctor, Sallaba, disagreed for days about what was wrong with him. Closset’s working diagnosis was “a deposit on the head,” an era-appropriate term for brain swelling that explains almost nothing. Days before the end, Sallaba told the household plainly: “Mozart is lost, it is no longer possible to restrain the deposit.” Neither doctor opened the body to look. A legally required check of the corpse for signs of foul play found nothing unusual, but that is not the same thing as an examination that could diagnose anything. Vienna’s death register records the cause in one German phrase, filled in under a law that asked for a description, not a diagnosis: hitziges Frieselfieber, “acute miliary fever.” It names the rash. It says nothing about what put it there.

The Roadblock

Every theory of what killed Mozart has to work from the same handful of secondhand accounts, and nothing else. No autopsy was performed. No prescription record survives to say exactly what his doctors gave him. No chart, no specimen, no case notes: nothing physical from his final two weeks exists to test a diagnosis against. Even the most detailed eyewitness account, Sophie Haibel’s, was set down in a letter in 1825, thirty-three years after she watched him die, by which point her memory of specific symptoms and their order had to compete with three decades of the story being retold.

The last physical possibility died too. A 2006 DNA analysis, run by Innsbruck University and the U.S. Armed Forces DNA laboratory, compared a skull long claimed to be Mozart’s against remains believed to be his niece’s and grandmother’s. None of the three samples matched each other. There is no verified body and no confirmed grave. Now there is no genetic anchor either, nothing left to exhume that could settle a medical question this way.

Best Guesses

Poststreptococcal kidney failure

In 2009, physicians in Amsterdam, Vienna, and London went past Mozart’s own case file, into Vienna’s civic one instead. They pulled the city’s official death register for the months around his illness, compared it to the same months in neighboring years, 5,011 deaths in all, and found a real spike in fatal edema among young men that winter. Their proposal: a streptococcal infection that progressed to poststreptococcal glomerulonephritis, a kidney inflammation that produces exactly the severe, whole-body swelling every account of his final weeks describes. It’s the one theory built on a population record instead of just his symptoms. It still can’t prove he had that epidemic’s disease rather than something else that swells a body the same way.

Trichinosis from undercooked pork

Forty-four days before he fell fatally ill, Mozart wrote Constanze an offhand letter mentioning a meal of pork cutlets. In 2001, infectious-disease specialist Jan Hirschmann built a case around that single line: trichinosis, a parasite from undercooked pork, produces fever, limb pain, swelling, and rash on a delayed timeline that lines up with Mozart’s dates about as well as any theory here does. The letter itself is just a man mentioning what he ate, not reporting symptoms, and trichinosis was common enough at the time that eating pork proves nothing on its own; weighing it against the roughly 150 other diagnoses on record, a colleague of Hirschmann’s called the whole question “virtually unknowable.” None of those 150 explain the 44-day gap the way this one does.

Acute rheumatic fever

This was the twentieth century’s default answer, and it comes from the closest thing this case has to expert testimony: Eduard Guldener von Lobes, Vienna’s senior city medical officer, who consulted daily with Closset though he never examined Mozart himself. Writing in 1824 to knock down the poisoning rumor, he described a “rheumatic and inflammatory fever” so widespread that winter that “few persons entirely escaped its influence,” with several Viennese dying of the same symptoms. A 2000 clinical panel at the University of Maryland, physician Faith Fitzgerald and Cornell musicologist Neal Zaslaw, revisited the case and backed this diagnosis. Its weak point: the disease’s signature markers, joint pain that migrates from limb to limb, heart inflammation, are barely mentioned in what survives of his final two weeks, which dwell on swelling and fever instead.

Poisoned by his doctors’ own cure

Closset had reportedly been dosing Mozart with antimony, a standard treatment of the era for depression and fatigue, and in 1991 physician Ian James argued the medicine, not any disease, killed him. Antimony poisoning causes swollen limbs, fainting, pustular eruptions, and kidney damage; period antimony was routinely contaminated with arsenic too. No prescription or apothecary record survives to confirm what dose, if any, Mozart actually received, so the case rests on symptoms, not a paper trail. But Mozart’s son and Sophie Haibel each independently mentioned a foul odor around him in his last days, which James read as consistent with the diagnosis, and Closset bled him the night before he died: by Constanze’s account, his strength “visibly ebbed” afterward, and he never woke again.

The Verdict

The one physical test this case could still have run has already failed. The 2006 DNA comparison didn’t just come back inconclusive on Mozart’s skull; it closed off exhumation, the one route that has cracked comparable cases elsewhere, and left behind it no confirmed grave, no verified remains, no medical record. What’s left to search is paper: a Viennese apothecary’s ledger that might record what Closset actually prescribed that winter, or a hospital register from the epidemic the 2009 study found, naming other patients well enough to compare symptoms against Mozart’s in more than outline. Absent that, this stays a contest between four readings of the same secondhand pages: Guldener’s memory, Sophie’s letter, a death register with one non-diagnosis on it. Two hundred and thirty-five years on, nobody has found a document that outranks them. The body that could have ended the argument has been unrecoverable for over two centuries.