Those extreme measures still will not end the epidemic completely. But the United States cannot long endure in a state of suspended animation, nor can the nation easily bear the cost of repeated lockdowns. That’s why it is also critical to fund and implement the safety measures necessary to let Americans get back to work, school and play without a recrudescence of the virus.

In fact, a nationwide lockdown should be seen as only the first step in a long fight that will proceed at a different pace in different parts of the country. In New York, where doctors and nurses dressed in trash bags and bandannas are desperately fighting to contain the virus even as bodies pile up, the crisis is upon us. In three weeks, when case counts in New York may be peaking, outbreaks in other parts of the country might just be entering a phase of deadly exponential growth. The virus may complicate matters even further by receding in late spring or summer, only to re-emerge in the fall or winter.

We need to prepare for what’s ahead.

Test, Test, Test

The virus will almost certainly re-emerge as individual states and cities start to lift the strictures of social distancing and shelter-in-place — but, ideally, that re-emergence will look more like a string of smaller brush fires than one raging forest fire. Health officials will not be able to detect those brush fires, or keep them from growing, without diagnostic tests. They will need enough tests both to survey the population at random and to diagnose patients who experience symptoms. They will also need the capacity to isolate those who test positive, and to identify, quarantine and monitor their contacts. If those contacts develop symptoms, they’ll need to be able to test them, too.

To build such capacity, the federal government will have to invest in the nation’s undervalued and deeply strained public health system: more funding will be crucial, but it will not be enough. State and federal leaders should work together, now, to create a public works corps to assist epidemiologists with contact tracing, to erect thousands of drive-through testing sites, and to do the work of infection control in nursing homes and homeless shelters. Some states are already doing this on their own, but others will need federal funding — perhaps in the form of block grants.

Antibody tests, which can determine whether someone has been exposed to the virus and may therefore be immune, will help get people back to work safely, allowing individuals and public health authorities to gauge who can proceed without worry, and who needs to take additional precautions. Scientists, in America and elsewhere, have already developed such tests. The federal government should orchestrate production of the tests in the necessary numbers.