Atul Gawande: Amid the coronavirus crisis, a regimen for reëntry

In places around the world, lockdowns are lifting to various degrees—often prematurely. Experts have identified a few indicators that must be met to begin opening nonessential businesses safely: rates of new cases should be low and falling for at least two weeks; hospitals should be able to treat all coronavirus patients in need; and there should be a capacity to test everyone with symptoms. But then what? What are the rules for reëntry?