Top infectious disease expert Dr. Anthony Fauci says antibody tests, which show who has already been infected with the coronavirus, will be available soon.

“Within a period of a week or so, we're going to have a rather large number of tests that are available,” Fauci told CNN’s Alisyn Camerota.

Fauci, the director of the National Institute of Allergy & Infectious Diseases, said testing of people who currently have the coronavirus and antibody tests will be done in parallel.

Fauci also said the prospect of Americans carrying certificates of immunity to prove they have tested positive for the antibodies to the coronavirus might "have some merit under certain circumstances." Immunity certificates are being discussed in the White House coronavirus task force meetings, Fauci said.

"It's one of those things that we talk about when we want to make sure that we know who the vulnerable people are and not."

Fauci declined to give a concrete date when the US can reopen businesses and begin to relax restrictions. “The virus kind of decides whether or not it's going to be appropriate to open or not,” he said. “I would want to see a clear indication that you are very, very clearly and strongly going in the right direction. Because the one thing you don't want to do is you don't want to get out there prematurely and wind up back in the same situation,” he added.

Fauci said that Americans should still practice social distancing guidelines during Passover and Easter. He predicted there will be many deaths in the next week, but “deaths tend to lag behind what the driving elements of the outbreak are,” and there should be fewer hospitalizations and intubations.

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