And if they might have some immunity, it would certainly offer some reassurance as families decide if it's safe to go back to work tonight.

We're with the researchers with an experimental test, checking for antibodies, a simple pin prick.

But can the federal government do they have the ability to get tens of millions of these tests ready and quickly what they said about that today?

Here's A B C's Kaylee Hartung Tonight tonight on the front lines of a key battle in the fight to get America back to work.

A line of people in Northern California waiting for an antibody test to determine whether they've been exposed to the Corona virus without knowing it and may now be immune.

The heater reopening is going to be testing the antibody testing in California, part of a USC Stanford study requires just a drop of blood, a simple pinprick.

They say it costs about 10 bucks and results are available in about 10 minutes $10.10 minutes.

Protest and you are gathering incredibly valuable information.

We can do this on a very large scale if you want.

The federal government has yet to deploy a nationwide test.

New York state, the epicenter of the crisis, is developing its own, but they're only able to perform a few 1000 tests a week.

It's not enough if you want to reopen on a meaningful scale and reopen quickly, we need unprecedented mobilization where government can produce these tests in the millions today.

Governor Cuomo, calling on President Trump to use the Defense Production Act to make private companies produce antibody tests.

But today from the White House, there's not a lot of issues with testing.

The president has downplayed the need for nationwide testing to diagnose Covert 19 or detect whether a person has had the virus and is now possibly immune.

You wanna have it and we're going to see if we have it.

You need it?

No.

Is it a nice thing to do?

Yes, we're talking about 325 million people, and that's not gonna happen.

But Dr Anthony Fauci says, testing his key and today announced the federal government is closing in on an antibody test within a period of a week or so, we're gonna have a rather large number of tests that are available.

President Trump now making this pledge.

We're confident that the production will scale up to tens of millions of tests very quickly.

A lot of eyes will be washing to see if that actually comes to fruition.

And Kaylee with us tonight, the president doctor found.

Two were both asked today, Kaylie whether Americans might one day have to carry some sort of proof that they have immunity from the virus.

Yeah, David Doctor found.

She was asked if he could imagine that day when Americans would carry around a so called certificate of immunity, he said, It's possible.

It's something.

They're disgusting, he says.

We need to make sure we know the difference between who's still vulnerable to infection and who's not.

David Kaylee Hartung, who has recovered from Corona virus herself, and we're glad to see that Caylee.

Thanks for reporting tonight.

Hi, everyone.

George Stephanopoulos here.

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