This is true, but you don't need blanket testing to have adequate testing for estimation of community spread. There is a fantastic video here[1] that covers the

This is true, but you don't need blanket testing to have adequate testing for estimation of community spread. There is a fantastic video here[1] that covers the specifics, but basically we know enough about how the virus spreads that if we just track who is in the hospital or dead from the virus, we can estimate its state of community spread, and thus know when to lock down. [1] https://www.youtube.com/watch?v=mCa0JXEwDEk https://www.youtube.com/watch?v=mCa0JXEwDEk