Despite a growing death toll from the novel coronavirus, pressure is mounting on U.S. governors and local authorities to lift social distancing measures and let millions of Americans go back to work.

But that raises an important question: Exactly who should go back to work first?

David Ostrov, a virologist at the University of Florida, has drawn up a checklist, one that ensures only the lowest-risk people take the lead as the United States reopens for business.

The checklist begins, but doesn’t end, with an antibody test, which determines whether a person has been exposed to the virus.

There’s a good reason for that, Ostrov told The Daily Beast. “People talk as if the presence of antibodies means that a person is immune,” Ostrov said. “The presence of antibodies actually means a person has been exposed .”

Catch a virus and your immune system will get to work churning out specific defenses against that virus. These antibodies are your body’s weapons against pathogens. But studies have made clear that exposure to SARS-CoV-2 doesn’t result in immunity to SARS-CoV-2.

In that way, the novel coronavirus is like HIV, the virus that causes AIDS. No one is immune to HIV, which is why after decades there’s no vaccine.

Under Ostrov’s system, you can go back to work if you:

Test positive in an antibody test;

Test negative for SARS-CoV-2 RNA;

Have no history of COVID-19, the respiratory disease caused by the coronavirus;

Show no symptoms of COVID-19;

Are younger than 65 and have no history of asthma, heart disease, or diabetes

Ostrov’s checklist does several things. First, it determines whether you’ve been exposed to SARS-CoV-2. If you haven’t, stay home. We don’t know yet whether you’re vulnerable to the virus.

Then, via the RNA check, it asks whether you’ve caught the virus and are still capable of spreading it to others. People exposed to SARS-CoV-2 aren’t contagious forever.

Want the gory details? A team led by German military virologist Roman Wölfel found “prolonged viral shedding in sputum”—that is, viruses in your spit—well into the second week of infection. After day 10, the viral load might shrink to just 100,000 copies of the pathogen per milliliter of sputum. It could take weeks for someone to become more or less totally non-contagious.

Some experts might be willing to stop at Ostrov’s second checkpoint. “People who score positive for the antibody test and negative for detectable virus would be the best candidates to go back to work since they are likely to be resistant to reinfection with SARS-CoV-2 at all, and would be much less likely to get severe disease even if they did get reinfected,” Stephen Jameson, a University of Minnesota pathologist, told The Daily Beast.

But Ostrov doesn’t stop. His checklist goes on to ask whether, when you caught the virus, you also got sick from it.

The majority of infected people are asymptomatic, meaning they carry the virus without ever knowing it. Ostrov wants asymptomatic carriers of the virus—people we know for sure can tough it out—to be the first to staff our factories, shoe stores, and movie theaters.

But not all asymptomatic carriers should risk going back to work. If you’re over the age of 65 and have a history of asthma, heart disease or diabetes, you shouldn’t take any chances. We think you could resist a second wave of COVID-19, but we’re not quite sure. “Immunology is complicated,” Ostrov said.

At the moment, it’s tough to administer Ostrov’s checklist. Ideally, authorities would have ample supplies of simple, fast tests. Take your test, reveal your medical history, and off you go, back to work at Lady Foot Locker.

The problem is, novel coronavirus test kits of all sorts are in short supply owing in part to poor planning at the federal level. “I hope that we are headed towards a simple saliva test that could detect the virus and antibodies,” Ostrov said. “This would help identify low-risk individuals.”

Some states are doing better than others moving through some or all of Ostrov’s checklist. California Gov. Gavin Newsom said he’d reopen the state’s economy only after widespread testing for both antibodies and virus RNA.

To that end, California authorities have ordered hundreds of thousands of swab tests (which detect the virus) and more than a million serology tests (which detect antibodies).

Georgia, by contrast, for weeks had one of the lowest rates of testing in the entire country. But Georgia Gov. Brian Kemp also was among the first to announce a gradual end to social distancing measures, starting Friday.

Even President Donald Trump, who recently took to Twitter to urge residents of Virginia, Michigan, and Minnesota to “liberate” their states from stay-at-home orders, said Kemp’s decision to re-open George has come “too soon.”