'Go and get 'em, folks': All adults in US now eligible for COVID-19 vaccine

All adults in the United States are now eligible to receive a COVID-19 vaccine, another major milestone reached in the ongoing effort to vaccinate the population against the virus and defeat the pandemic. 

Individuals age 16 and up can register for vaccination in every U.S. state, as well as in Washington, D.C. and Puerto Rico. The announcement Monday by the White House meets the April 19 deadline set by President Joe Biden earlier this month.

"Everyone 16 and older in America is eligible for the shot today. Go and get ‘em, folks," Biden tweeted Monday.

"We have enough of it. You need to be protected. And you need, in turn, to protect your neighbors and your family. So please, get the vaccine," Biden said in a pre-recorded video shared earlier Monday.

Half of all U.S. adults — or more than 131 million people — have received at least one dose of a vaccine, the U.S. Centers for Disease Control and Prevention reported. Roughly 84.2 million adults, or about 32.5% of the total adult population, have been fully vaccinated.

The U.S. is now averaging 3.2 million doses administered per day, according to the CDC.

The country cleared the 50% mark for adults just a day after the reported global death toll from the coronavirus topped a staggering 3 million, according to totals compiled by Johns Hopkins University, though the actual number is believed to be significantly higher.

Hawaii, Massachusetts, New Jersey, Oregon, Rhode Island and Vermont were the last states to expand vaccine eligibility, which opened to younger adults residents on Monday.

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WASHINGTON, DC - APRIL 15: President Joe Biden announces new economic sanctions against the Russia government from the East Room of the White House on April 15, 2021 in Washington, D.C. (Photo by Chip Somodevilla/Getty Images)

Biden had initially set the vaccine eligibility deadline for states to May 1 but moved the date up as vaccine supply and rollout efforts increased.

The White House was also set to launch a targeted media blitz this week to promote the mass vaccination campaign, including a partnership with Twitter and Facebook to send push notifications informing users of their eligibility, Axios reported.

Johnson & Johnson’s COVID-19 vaccine, one of the three vaccines currently being administered in the U.S., was dealt a blow last week when federal health regulators recommended a pause of the single-dose shot after reports of rare blood clots. 

The nation's top infectious diseases expert indicated Sunday that the government will likely move to resume use of J&J's COVID-19 vaccine this week, possibly with restrictions or broader warnings after reports of some very rare blood clot cases.

Dr. Anthony Fauci, in a series of news show interviews, said he expects a decision when advisers to the CDC reconvene on Friday to discuss the pause in J&J’s single-dose vaccine.

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"I would be very surprised if we don’t have a resumption in some form by Friday," he said. "I don’t really anticipate that they’re going to want it stretch it out a bit longer."

Fauci, who is Biden’s chief medical adviser, said he believed that federal regulators could bring the shots back with restrictions based on age or gender or with a blanket warning so that it is administered in a way "a little bit different than we were before the pause."

The J&J vaccine has been in limbo after the CDC and the Food and Drug Administration said last week they needed more evidence to decide if a handful of unusual blood clots were linked to the shot — and if so, how big the risk is.

The reports are rare — six cases out of more than 7 million U.S. inoculations with J&J vaccine. The clots were found in six women between the ages of 18 and 48. One person died.

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The acting FDA commissioner had said she expected the pause to last only a matter of days. Still, the decision last Tuesday triggered swift action in Europe and elsewhere.

Fauci said he doubted very seriously that the U.S. would permanently halt use of the J&J vaccine.

"I don’t think that’s going to happen," he said. "The pause was to take a look, make sure we know all the information we can have within that timeframe, and also warn some of the physicians out there who might see people, particularly women, who have this particular adverse event, that they treat them properly."

"I think it’ll likely say, ‘OK, we’re going to use it. But be careful under these certain circumstances.’"

More than 7.8 million doses of the J&J vaccine have been given in the U.S., the vast majority with no or mild side effects. Authorities stressed they have found no sign of clot problems with the most widely used COVID-19 vaccines in the U.S. — from Moderna and Pfizer — and urged Americans to get vaccinated.

Moderna has been given an emergency use authorization for those age 18 and up, while Pfizer has been cleared for those 16 and over.

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This story was reported from Cincinnati. The Associated Press contributed.