[agrenader]

So does flu. From https://www.cdc.gov/flu/symptoms/symptoms.htm possible serious complications triggered by flu can include inflammation of the heart (myocarditis), brain (encephalitis) or muscle (myositis, rhabdomyolysis) tissues, and multi-organ failure (for example, respiratory and kidney failure). Flu virus infection of the respiratory tract can trigger an extreme inflammatory response in the body and can lead to sepsis, the body’s life-threatening response to infection.

[snapetom]

Just my own anecdote...

In 2013, I was in ok shape, late 30's, running maybe about 15 miles/week with some gym activity. I was suddenly hospitalized for 4 days with pneumonia and "something else." About four months later, I got on a treadmill and couldn't run for more than a minute.

Long story short, I was diagnosed with viral cardiomyopathy. A virus basically comes in, fucks up your heart, then leaves. Myocarditis was the method in my case. They never ran a test to see what virus, because at that point, there wasn't any reason to. The damage was done. My ejection fraction was at 15% (50-55% is normal). I was given a defibrillator vest to shock me if I collapsed, and eventually I got a permanent implant.

In various conversations with cardiologists, they mentioned that it's believed to be much more common than they once thought. My primarily cardiologist said the week prior to me, she had a young, perfectly healthy male, in his early 20's that had a very similar hospitalization event. His was so bad they immediately put him on the transplant list.

[nradov]

I suspect that a high percentage of chronic medical conditions that people deal with were triggered at least partly by undiagnosed viral infections. But that's just conjecture, there's no way to prove it.

[elcomet]

Did you eventually recover ?

[saiya-jin]

permanent implant doesn't sound like a recovery one would wish for

[snapetom]

Not 100%. About a third of people recover fully within 3-4 months, but if it's beyond that, you're likely stuck. I am, however, one of the few that got up to 80-90% of normal a couple of years afterwards. My primary cardiologist said in 20 years of practice, I was one of the only three patients that he treated that did this.

I credit returning to long distance running. I don't recommend it as a treatment. Not scientifically studied and was/is definitely against doctor's orders.

[neilwilson]

And as I discovered in my family hyponatremia which has left my mother on anti-seizure tablets for the rest of her days.

Don’t underestimate flu

[rob74]

Yes, but with the flu, most people (a) know that they had it and (b) are aware that they should take it easy with the training for a few weeks after they get well again. With Covid, apparently there is danger of myocarditis even for mild or asymptomatic cases...

[nradov]

Mild or asymptomatic cases are also common with influenza.

https://wwwnc.cdc.gov/eid/article/22/6/15-1080_article

Some of those cases do have heart problems.