SAN FRANCISCO (KRON) — Dr. Anthony Fauci is now saying it will likely be mid-summer before the majority of Americans will be able to get the COVID-19 vaccine.

The infectious disease expert and White House chief medical adviser last week predicted that by April, it would be “open season, namely virtually everybody and anybody in any category could start to get vaccinated.”

Now, speaking on CNN Tuesday, Fauci said, “That timeline will probably be prolonged, maybe into mid-to-late May and early June,” the network’s chief White House correspondent, Kaitlan Collins, tweeted.

“It may take until June, July and August, to finally get everyone vaccinated,” Fauci said.

Recently, San Francisco and Los Angeles had to temporarily close mass vaccination sites because of the low supply of doses. Even so, new sites are popping up all over.

On Feb. 11, President Joe Biden said the final contracts for 100 million more Moderna and 100 million more Pfizer vaccines have been signed, expecting enough vaccines for 300 million Americans by the end of July.

The U.S. is on pace to exceed Biden’s goal of administering 100 million vaccine doses in his first 100 days in office, with more than 26 million shots delivered in his first three weeks. Meanwhile, Biden is moving to ease supply bottlenecks and ensure the nation has enough of the current two-dose vaccines to protect 300 million Americans by the end of summer.