This approach uses two complementary strategies. The first relies on tests to target social distancing more precisely. The second relies on protective equipment that prevents the transmission of the virus. Adopting these strategies will require a massive increase in our capacity for coronavirus testing and a surge in the production of personal protective equipment.

Resources, not scientific breakthroughs, are needed to expand our capacity for virus tests. If we commit to this type of expansion, technological innovations will continue to lower the cost and increase the speed of the existing tests. In many locations it has taken days to process SARS-Cov-2 tests. On Saturday, the Food and Drug Administration said it would allow a Silicon Valley company, Cepheid, to start selling a test that provides results in 45 minutes. Other firms and research groups (among them Sherlock Biosciences and the German Center for Infection Research) are working on scalable alternatives. Many hospitals are developing their own tests.

These newer tests could be so much less expensive and so much more convenient that it will be possible to test and retest everyone, not just those with symptoms. Frequent virus tests will let us identify and isolate someone who is infectious days before symptoms develop.