Since they are defining 60 years old as a breakpoint... I don't think there are a lot of us under 60 here, I could be wrong. I am in good aerobic shape and hike daily at high elevation, and don't get sick (I had over a year of sick leave built up when I retired from my career job) but, like my siblings, I have mild diabetes, so I have the top trouble underlying condition that Sanjay mentions. I think i would be able to fight it off, but i have 4 siblings in their 80s. So you are right, this is getting pretty real pretty fast.