Dr. Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health, shut down CNN’s Jim Acosta on Tuesday for suggesting that President Donald Trump did not act early enough to stop the spread of the coronavirus.

Fauci’s remarks came in response to Acosta asking Trump and members of the Coronavirus Task Force how the predictions of the number of Americans who will die from the virus would be different if the administration had asked earlier.

“Just to underscore what Dr. Birx was saying, if there was no virus in the background, there was nothing to mitigate,” Fauci said. “If there was virus there that we didn’t know about, then the answer to your question is probably yes. Now the only trouble with that is that whenever you come out and say something like that, it always becomes almost a sound bite that gets taken out of context, but I think that’s very important, what Dr. Birx has said, is that if there was covert infections here that we didn’t know about, and we didn’t mitigate them, that they would’ve made a difference. If there was virtually nothing there, then there’s nothing to mitigate. And I don’t know the answer to your question.”

“But they were early. They started early,” Acosta claimed. “We were watching South Korea, excuse me, and China and Italy, and we weren’t taking action when those countries were spiking.”

“In a perfect world, it would have been nice to know what was going on” in China,” Fauci responded. “We didn’t, but I believe Jim, that we, we acted very, very early in that.”

Dr. Deborah Birx said during the press conference that any lack of preparation from U.S. officials in responding to the coronavirus pandemic was due to the fact that “we were missing a significant amount of the data” from China.

WATCH:

TRANSCRIPT:

CNN’S ACOSTA: This may be an uncomfortable question, what would the models have looked like that Dr. Birx and Dr. Fauci showed us if we had started the social distancing guidelines sooner in February or January when China and South Korea were doing those sorts of things? … If we had started these practices sooner, could these models be different right now?

PRESIDENT TRUMP: Yeah, I’m going to let them answer the question, but remember this. And again, I say it and everybody says it. You know who says it better than anybody is Dr. Fauci. I had a decision to make. Maybe it was my biggest decision. China was heavily infected, and thousands and thousands of people were coming from China to the United States. And against the wishes, not even wishes, but they disagreed with the decision. I made a decision to stop China from coming in. Took a lot of heat, even from China. They weren’t exactly happy. I just made a trade deal, a big one, $250 billion trade deal. And I’m shortly thereafter saying, “You can’t come into our country.”

That was a big decision. That was earlier than the date you’re talking about. So that was a big decision. That was probably, and by the way, not because I did it, that was probably the biggest decision we made so far. But if you look at the one graph, the problem New York has is New York started late, but the other ones didn’t start so late. Now New York is also more complicated, because for obvious reasons, but it got a late start. But do you maybe want to answer those questions?

DR. BIRX: I don’t know if you can go back to slide two, because I wanted to explain two things that I think is really important, because we had a lot of questions about mortality and what it meant. Okay. So you see this confidence interval? So here’s the line. This is the confidence interval. This is where we have the ability to push it down. So you have a large confidence interval around the line. And so we’re trying to move that gray down tighter and below the dotted line. So I think that’s really important.

And then if you can go to the next slide. So we really can’t answer your question until we can get antibody testing out there. Because what we can’t tell you, and we can always do this, there’s always samples in hospitals and other things. It’s the way we really define the HIV epidemic in the United States. We were able to go back to blood samples when we had the test and really find out where it was and what was going on. We really need to look in here. And really see was there virus significantly circulating in early March and late February? And what did it look like? And where was it? And was it all in the metro areas? And I think that’s what Dr. Fauci and I are very, very focused on is getting serology testing out there to really figure out when it came, and really have those samples to be able to do that.

CNN’S ACOSTA: You understand the painful part of my question, and please, I don’t mean to put you on the spot-up there may be Americans at home saying, “If we had started this sooner, we might not have 100000 to 200000 Americans dying.”

DR. BIRX: No, we understand, but we can’t answer it until we see that. Well, that makes an assumption that it was here, a lot back here, that we didn’t see. And until we have the antibody tests, I can’t really answer that.

DR. FAUCI: Just to underscore what Dr. Birx was saying, if there was no virus in the background, there was nothing to mitigate. If there was virus there that we didn’t know about, then the answer to your question is probably yes. Now the only trouble with that is that whenever you come out and say something like that, it always becomes almost a sound bite that gets taken out of context, but I think that’s very important, what Dr. Birxs has said, is that if there was covert infections here that we didn’t know about, and we didn’t mitigate them, that they would’ve made a difference. If there was virtually nothing there, then there’s nothing to mitigate. And I don’t know the answer to your question.

CNN’S ACOSTA: But they were early. They started early. We were watching South Korea, excuse me, and China and Italy, and we weren’t taking action when those countries were spiking.

DR. FAUCI: In a perfect world, it would have been nice to know what was going on there. We didn’t, but I believe Jim, that we, we acted very, very early in that.

VICE PRESIDENT PENCE: Can I speak to that too as well? President made reference to the fact, January 31, he suspended all travel from China. Shortly thereafter, we issued strong travel advisories for the sections of Italy implicated and sections of South Korea, and we reached agreements with those countries to screen all passengers from all airports coming into the United States of America. The president’s initial efforts were designed at preventing the Coronavirus from coming into the United States. And what our experts have told us again and again at the Coronavirus task force is that those actions bought us a significant amount of time on this curve to respond with kind of mitigation efforts, standing up resources, testing and supplies that are in effect.

But we went from a prevention strategy the President acted on before the month of January was over to a mitigation strategy, which continues to this day. And if I can also say just to every American, all the questions about resources are very important. And I can assure you that the President and our task force are preoccupied with these issues and working with governors hour by hour to meet those needs. But if Americans will put into practice these guidelines for another 30 days, they’ll do their part to lower the curve and save lives, most importantly, and limit the burden on our hospitals and our healthcare system in the country significantly.

And so make no mistake about it. While we’re going to work our hearts out, leave no stone unturned, to find the resources, the masks, the ventilators that we need, and we are going to meet that moment with the full energy of the American economy and the whole of the American government. The American people have a role to play in preserving that medical capacity in a way that will ensure that people that are caught up in the Coronavirus, particularly those that are vulnerable to the most serious outcomes, which are seniors with serious underlying health conditions or anyone with an immunodeficiency, have the resources, the support and the health care that every American family would want their loved one to have.

PRESIDENT TRUMP: I do believe we were very early, but I also think that we were very smart, because we stopped China. We had never done that before. You know, we had never closed our borders before, as I read. I read. I don’t know, maybe that’s not right. And Dr. Fauci had also said that was, I think it was maybe the biggest moment, because we were stopping the source. We were stopping the infection. But we also stopped Europe very shortly thereafter. That was a big decision. That was not an easy decision either. I stopped them a long time before people started stopping anywhere. So we stopped China, we stopped Europe, we stopped all of Europe. And then ultimately we stopped UK, Ireland.