[tallanvor]

Yeah. No known preexisting conditions is very different from no preexisting conditions. That being said, it's certainly possible that she was just unlucky and the virus hit her harder than normal for people her age, or she caught some other bug at the same time.

[8fingerlouie]

She could have a specific mutation in her DNA that protects against other things, that somehow makes COVID-19 worse.

Like the CCR5-Delta32 mutation makes 10% of Europeans resistant to HIV (https://www.sciencedaily.com/releases/2005/03/050325234239.h...).

There are other mutations that appears to combat virus more effectively, but who's to say that there are not mutations that are beneficial for some disease, but catastrophic for others ?

[throwqwerty]

>No known preexisting conditions is very different from no preexisting conditions.

but you can easily have regular checkups and still have an undiscovered (unknown) pre-existing condition. so what is the difference?

[ProstetnicJeltz]

Also we need to remember what the relevant pre-existing conditions here are.

I think most people are immediately thinking severe asthma, COPD, recent or current cancer treatment; and while all of those elevate your risk, they aren't the most common comorbidities.

The key co-morbidities are high blood pressure, heart disease and diabetes.

Only heart disease seems obvious - high blood pressure is almost standard, and diabetes is often managed well to the point of invisibility.

The cardiac link appears interesting. Patients who are given ECMO, a complete lung bypass alternative to ventilators, have still died after their lungs recovered.

[zuminator]

But assuming this person had an unknown pre-existing condition is no comfort at all. It just means that anyone could equally have an unknown pre-existing condition that would similarly render then susceptible.

[lopis]

The thing is how do you know you don't have any commodities. Specially if you're in your 20s lots of congenital defects might have not had the chance to be a problem.

[C1sc0cat]

It can happen I recall a student where I worked, broke his leg in an evening cricket match, he died before morning.