Older people severely affected by COVID-19 also exhibit such immune hyper-reactivity, suggesting that they may have been primed by a pathogen exposure in the 1950s, before the less vulnerable population was born.
So, while old people must strenuously avoid being infected regardless of their current health status, for everyone else, particularly young adults and children, a different policy should be in effect. Vaccination is the safest way to establish “herd immunity,” the condition in which the general population is largely resistant to an infection, and its members, even if they become infected, are therefore incapable of spreading it. Until there is a vaccine for COVID-19, however, the only route to herd immunity is for those who can be infected without getting sick, become so.

https://www.counterpunch.org/2020/03...make-it-worse/