The CDC is working on this, for example https://www.statnews.com/2020/04/04/cdc-launches-studies-to-get-more-precise-count-of-undetected-covid-19-cases/ https:

The CDC is working on this, for example https://www.statnews.com/2020/04/04/cdc-launches-studies-to-get-more-precise-count-of-undetected-covid-19-cases/ https://www.statnews.com/2020/04/04/cdc-launches-studies-to-...