Try 'risk stratification virus' on Google Scholar to start to get a sense of the research field. For specifics on Covid, I think look for materials from John I

Try 'risk stratification virus' on Google Scholar to start to get a sense of the research field. For specifics on Covid, I think look for materials from John Ioannidis (a long-time personal hero of mine) if you're interested in the research side, or David Katz (also someone I have followed closely for a while - kind of a MD version of Michael Pollan) if you're interested in the clinical side. Both have published papers if that's a good medium for you, and both have solid videos on youtube if that's more your speed.