They came up with the call with an open letter.

"Of all the nations in the world, we've had the most deaths from COVID-19. At the same time, we're in the midst of 'reopening our economy,' exposing more and more people to coronavirus and watching numbers of cases -- and deaths -- skyrocket," they said in the letter addressed to the Trump administration, members of Congress and state governors.

"Right now we are on a path to lose more than 200,000 American lives by November 1st. Yet, in many states people can drink in bars, get a haircut, eat inside a restaurant, get a tattoo, get a massage, and do myriad other normal, pleasant, but non-essential activities," said the letter.

The best thing for the nation is not to reopen as quickly as possible, it is to save as many lives as possible.

They urged enough daily testing capacity to test everyone with flu-like symptoms plus anyone they have been in close contact with over the last two weeks, a workforce of contact tracers large enough to trace all current cases, and more personal protective equipment to keep essential workers safe.

"Shut it down now, and start over," they appealed.

Non-essential businesses should be closed. Masks should be mandatory in all situations, indoors and outdoors, where people interact with others, they said.

"We need that protocol in place until case numbers recede to a level at which we have the capacity to effectively test and trace. Then, and only then, we can try a little more opening, one small step at a time," said the experts.

More than 4.08 million COVID-19 cases have been reported in the United States with the fatalities surpassing 144,900 as of Friday afternoon, according to a tally by Johns Hopkins University.