WASHINGTON — Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said Friday that Americans will most likely have to continue staying at home and practicing social distancing for “at least several weeks" amid the coronavirus outbreak.

“If you look at the trajectory of the curves of outbreaks and other areas, at least going to be several weeks,” Fauci said in an interview with Savannah Guthrie on the “TODAY” show.

“I cannot see that all of a sudden, next week or two weeks from now it's going to be over. I don't think there's a chance of that. I think it's going to be several weeks.”

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When speaking about whether it’s time for President Donald Trump to use the Defense Production Act to produce critical supplies, Fauci suggested that the U.S. should be doing everything in its power to slow the outbreak.

“I think we should do everything we possibly can do. I mean, in all sectors, because obviously as I've said so many times, when you think you're maybe overreacting, you probably are not acting as forcefully as you should. So as we've always said, we've got to try very much to stay ahead of the curve.”

This week, Trump predicted that the outbreak could dissipate by July or August. The White House announced restrictive national guidelines that advise people to work from home for 15 days, postpone unnecessary travel and limit social gatherings to no more than 10 people.

“We’ll see what happens after that,” Trump said at the White House coronavirus task force briefing Tuesday. “If we do this right, our country — and the world, frankly — but our country can be rolling again pretty quickly. Pretty quickly.”

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At the briefing Tuesday, Fauci, a key member of the task force, was asked how long will it take before officials will know whether the guidelines are actually flattening the curve.

“It probably would be several weeks and maybe longer before we know whether we're having an effect,” he said.

On Wednesday, a reporter asked Trump about a plan compiled by the Department of Health and Human Services that the outbreak could last as long as 18 months. Trump said, “No, we’re not seeing that at all,” when asked if he’s seen those estimates.