The challenge here is, I think, that the term 'asymptomatic' is heterogeneous. Sometimes it includes literally any possible issue, but often is limited to 'known symptoms of COVID-19'https://twitter.com/EricTopol/status/1308497379373404160 …
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I.e. when we say "30-40% asymptomatic" what we really mean is "30-40% of people will have an infection mild enough that they wouldn't note any symptoms to their physician" A minor distinction, perhaps, but important imo!
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