How do we know it's harmless for youth and young adults? You know what you've seen. Again, this is a novel virus. It's new. It could be setting up shop in your brain, heart, kidney, liver, semen -- wherever.

It could be invisibly weakening your lungs just enough that a flu can come through and kill you.

I would suggest a deep dive on mercury poisoning, radiation poisoning, lead poisoning, asbestos, and whatever other reminders you may find throughout history that assuming you know what nature is up to without the benefit of lengthy scientific review never turns out well for the cocksure.