After several weeks of coronavirus lockdown measures, with millions of people sheltering in place, there has been talk of reopening parts of the economy. Social distancing has been used effectively in some places to flatten the curve of infections and to slow the spread of the virus, but is it realistic to speak of getting back to business as usual anytime soon?

Yonatan Grad, assistant professor of immunology and infectious diseases at the Harvard T. H. Chan School of Public Health, said he understands the economic pressures.

“I think we will have to explore ways to open up,” Grad said. “And I think it is incumbent on us to figure out the way to do that, that is safest and most reasonable, while meeting our goal of trying to limit the threat to health care infrastructure.”

But — and it is a big but — Grad said he doesn’t think we are at a place where we can make informed decisions about what will be the safest way to reopen.

Being a scientist and a data-driven kind of guy, Grad is hungry for data. And according to him, there is simply not enough of it to understand how widespread coronavirus infections are. For Grad, the situation we now find ourselves in is something akin to driving a car without a dashboard. How can you navigate your way through a crisis if you don't even know if you have enough gas to get to your destination?

In fact, there is a growing chorus of voices calling for that “dashboard,” vital data that could be obtained through a dramatic increase in coronavirus testing. Grad and many others are convinced there needs to be much greater diagnostic testing and testing for COVID-19 antibodies to assess where things stand and to monitor the situation moving forward.

This week, a group of bipartisan experts released a “Roadmap to Pandemic Resilience” that described COVID-19 as a “profound threat to our democracy, comparable to the Great Depression and World War II.” The report said at least 5 million tests a day would be needed by early June to begin to safely open up parts of society. It also states that the number would have to increase to 20 million tests a day by late July to “fully re-mobilize the economy.”

To safely end the coronavirus lockdown for everyone would require not only drastically ramping up testing but also contact tracing and supported isolation for those with the disease, the authors of the report said.

Grad is a member of the external COVID-19 task force for Massachusetts, a state that under Gov. Charlie Baker’s leadership has taken the lead in contact tracing.

However, as Baker himself has admitted, when it comes to screening for the virus, there have been problems with the accuracy of some of the test kits currently available on the market. Tracking down every person infected with the virus could also be a significant challenge, given the massive spread of the disease and that as many as 25 percent or more could be asymptomatic.

Clearly, it’s a long road ahead. According to Grad, there are ultimately two ways that the pandemic ends. He said that we could eliminate the virus — which seems unlikely, given how widespread it is at home and abroad — or people will need to develop resistance to the disease through a vaccine or by so-called “herd immunity.”

As there is unlikely to be sufficient resistance built up to COVID-19, Grad said now is the time to start planning for the fall when there could be a resurgence of infections, coupled with the start of the flu season. The director of the Centers for Disease Control and Prevention, Robert Redfield, has warned that the combination could make the disease even more deadly.

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