Director of the National Institute of Allergy and Infectious Diseases Anthony Fauci recommended on Thursday that all states across the U.S. implement stay-at-home orders, at a CNN town hall.

Why it matters: The recommendation stands in contrast to President Trump's calls for "flexibility." Nearly 4o states have issued stay-at-home orders to promote social distancing as a way to combat the novel coronavirus — but the orders vary in strictness and duration.

Trump said at the White House coronavirus task force briefing on Wednesday that in states with fewer infections, "it's awfully tough to say close it down."

What he's saying: "I don't understand why that's not happening," Fauci said, per CNN, of a nationwide stay-at-home order. "As you said, the tension between federally mandated versus states rights to do what they want is something I don't want to get into. But if you look at what is going on in this country, I do not understand why we are not doing that. We really should be."

Background: The Trump administration has directed Americans to "work or engage in schooling from home whenever possible" for roughly a month, to "avoid discretionary travel, shopping trips, and social visits," and to "avoid social gatherings in groups of more than 10 people."

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