Random thoughts here, no links.
Perhaps the tracking of individuals at risk for a poor outcome from COVID-19 is backwards and who should be studied instead are those who HAVEN’T contracted the virus or did but had mild symptoms.
What is it they’re doing, or not doing, not limiting the study to vaccines? Are they eating more healthy? Exercising, or more spiritual, possibly into regular practices like meditation?
How, for example, are even those considered at risk for a poor outcome surviving with minimal complications? It would be interesting to learn what factors beyond one’s control, or choices they’re making that make a difference?
