What we're learning on that front and President Trump and his words today about a drug that he said could be a game changer in the fight against Corona virus.

But then moments later, the nation's top doctor on infectious diseases, Dr Anthony Fauci, was asked about it and offered a reality check.

Here's our senior White House correspondent, Cecilia Vega.

24 hours after President Trump declared a malaria drug would be made available almost immediately to help treat Corona virus, Dr Anthony Fauci declared, the drug has not actually been proven to help.

Is there any evidence to suggest that, as with malaria, it might be used as a prophylaxis against code?

I think the answer is no, and the evidence that you're talking about John is anecdotal evidence.

But President Trump pushed on, leading to a rare public rebuke by the nation's foremost expert on infectious diseases, may work, May network.

I feel good about it, that's all.

It is just a feeling, you know, smart guy, because you know the expression.

What the hell do you have to move?

So I've been right a lot.

Let's see what happens.

I would like Dr Factory if you don't mind to follow up on what the president is saying.

Should Americans have hope in this drug?

Right now?

The president feels optimistic about something.

His feeling about it.

It might be effective, but as a scientist, as we're getting it out there, you need to do it in a way, as while we are making it available for people who might want the hope that it might work.

You're also collecting data that will ultimately show that it is truly effective and safe under the conditions of covert 19.

Fundamentally, I think it probably is going to be safe, But I like to prove things first.

We'll have more on that, of course, in the days to come.

Cecilia.

In the meantime, what have you learned about a member of the vice president's office tonight?

David, this is just coming in from his office right now.

They say a member of his team has tested positive for the Corona virus.

Neither the president, they say, nor the vice president had close contact with this person who's not being identified.

But the vice president's office is saying that they are now going back to see exactly who this person had contact with here.

David again, a member of Vice President Mike Pence's office tonight, testing positive Cecilia Vega with the breaking news Sicilia.

Thank you, Hi, everyone.

George Stephanopoulos here.

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