Washington DC – President-elect Joe Biden’s goal of vaccinating 100 million Americans during his first 100 days in office got a seal of approval from the country’s top infectious disease expert on Sunday.

"The feasibility of his goal is absolutely clear, there’s no doubt about it," Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said on NBC’s Meet the Press.

He also voiced approval for steps Biden has outlined. The president-elect promised Friday to boost vaccine production and distribution as the coronavirus outbreak continues to rage.

"What the president-elect is going to do is where we need be," Fauci said.

Since last month, the United States has been using vaccines produced by Pfizer and Moderna. Fauci said he expects drugs made by Johnson & Johnson and AstraZeneca to get federal approval soon.

"We’re weeks away, not months away," he said. He also chalked up surprising revelations that the federal government doesn’t have a stockpile of vaccines for use in second doses due to a "misunderstanding."

Fauci said he’d been informed that feds initially held back some doses as Americans received their first of two shots, but stopped doing so "when it became clear that the ‘cadence’ of the flow of doses was really going to be consistent and reliable."

The doc also warned of new strains of Covid-19 emerging around the globe.

"People need to realize there’s more than one mutant strain," he said. "There’s one from the UK that’s essentially dominated. That’s the one that is actually is seen in the United States. There’s another more ominous one that’s in South Africa and Brazil."

"The thing we really want to look at carefully is that does that mutation lessen the impact of the vaccine?" Fauci continued. "And if it does ... then we’re going to have to make some modifications."