The disruption to everyday life in American caused by the coronavirus pandemic is the most severe Dr. Anthony Fauci has seen in the 36 years he's been the director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health. While there have been "an awful lot of challenges," this situation is different because of all the "unknowns" surrounding the virus, he said. 

"With regard to disruption of everyday life, we have not seen that before, but we've not had this kind of a situation before," he said on "CBS This Morning" Friday. "I mean, we've had pandemics. The 2009 H1N1 swine flu was a pandemic, but it was influenza. We were familiar with what influenza does, familiar with its seasonal capability. Right now, there are a lot of unknowns."

Concerns over the spread of coronavirus in the United States have canceled sporting events, music festivals and political rallies. Many schools have shut down and companies have asked their employees to work from home.

Just over 13,000 people have been tested for the virus in the United States, according to the COVID Tracking Project. More than 1,700 have tested positive. 

But there have been barriers for doctors to conduct coronavirus tests. The current system in place is "failing," Fauci said at a Congressional committee hearing Thursday. It "is not really geared to what we need right now," he said.

"That is being rapidly corrected," he said on "CBS This Morning." "We had a task force meeting yesterday, and we heard that the kinds of tests from the commercial sector that would be readily available is really very, very close right now. Very close."

Fauci said restrictions on who can be tested "have been lifted" by the Food and Drug Administration, and he hopes by next week, "If you go in, there's a good reason for you to get it, you're going to get a test."

"It's going to be graded. It's not going to all happen tomorrow or the next day," he cautioned.

Fauci also said even without widespread testing, mitigation measures should be taken to slow the spread of coronavirus. 

"The kinds of things you're hearing about which we call social distancing, which means staying away from crowds, doing teleworking, where appropriate, closing schools, canceling events that bring many, many people together. You can do that right now," he said. "Obviously we want to and will have considerably more testing in the future, but you don't wait for testing to do the mitigation. You can do it right now."

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