60% of US adults have received at least 1 dose of COVID-19 vaccine, CDC says

The U.S. reached a notable milestone Tuesday in President Joe Biden’s ongoing effort to fully vaccinate 160 million adults by the Fourth of July: the U.S. Centers for Disease Control and Prevention said 60% of American adults have now received at least one dose of a COVID-19 vaccine. 

Data from the CDC showed more than 154 million adults have now received at least one dose, while 122 million — or 47% of U.S. adults — are now fully vaccinated. 

Vice President Kamala Harris acknowledged the milestone on Twitter. "This is progress," she said while encouraging those who haven’t gotten the shot yet to do so. 

Earlier this month, Biden set a goal of 70% of adults to have received at least one dose of a COVID-19 vaccine by Independence Day, with 160 million fully vaccinated against the virus. He called on Americans to get the shot so the country "can celebrate our independence as a nation and our independence from this virus."

CDC data shows 56.3% of the population aged 12 and older has received at least one shot. Pfizer’s COVID-19 vaccine was given emergency approval last week by the Food and Drug Administration for those 12-15 years old. 

This week’s milestone comes on the heels of CDC easing mask guidance, saying those who are fully vaccinated no longer need to wear a mask indoors or outdoors and can stop social distancing in most places. Fully vaccinated means two weeks after the second dose of the Pfizer or Moderna COVID-19 vaccine, or two weeks after the one-dose Johnson & Johnson shot. Regardless of vaccination status, masks are still required on public transportation — buses, trains and planes — and in other settings like hospitals, prisons and homeless shelters.

The government’s updated guidance caused some confusion and sent businesses and states scrambling to adjust their rules. Some major retailers, including Target and CVS, are dropping their mask rules for fully vaccinated people because of the CDC change, while others are keeping them in place. 

The change was based on new science in recent weeks that supported easing the advice on masks and social distancing, according to Dr. Rochelle Walensky, the CDC director. She said new evidence showed COVID-19 vaccines work in real-world settings, are effective against virus variants and prevent the spread of the virus. 

In announcing the new advice, she also cited the drop in infections in the U.S., the wide availability of vaccines and the expansion to ages 12 and up for the shots.

"I want to be clear that we followed the science here," Walensky said at a White House briefing.

Dr. Anthony Fauci, the nation’s top infectious disease expert, on Tuesday acknowledged some "confusion" over the guidance, telling ABC News that the problem lies in that "we don’t have any way of knowing who is vaccinated and who’s not vaccinated."

Fauci said it’s "reasonable and understandable" that some businesses and localities are maintaining mask requirements because they can’t be sure of an individual’s vaccination history. But he added that it’s important to note those measures protect the unvaccinated from each other, and vaccines provide a high level of protection for those who have gotten them.

Children who are not yet vaccinated — including children under 12 who won’t be eligible for vaccines for months — should continue to wear masks indoors. Fauci said that recommendation could change as the CDC conducts more research and more Americans get shots.

Newly reported COVID-19 cases in the U.S. have continued to trend downward in recent weeks, and deaths in the country have hit their lowest level in 10 months. The number of lives lost has dropped to single digits in well over half the states and even hit zero on some days — a welcomed development after a tragic year that recorded grim milestones and put the U.S. at the top of the global death toll list at more than 586,000 people.

Biden on Monday also announced that the United States will share an additional 20 million vaccine doses with the world over the next six weeks — making a total of 80 million doses to be shared. The additional doses will come from existing U.S. production of Pfizer, Moderna or Johnson & Johnson vaccine stocks as they become available, he said.

The president said fighting the disease around the world "will help keep us safe here at home" and called it "the right thing to do," as countries like India face a massive surge in cases and record deaths.

RELATED: India reports highest single-day death toll to COVID-19 as cases begin to level off

In the last month, cases in India have more than tripled and reported deaths have gone up six times. A variant first identified in the country has also prompted global concern — most notably in Britain, where it has more than doubled in a week, defying a sharp nationwide downward trend in infections.

The Biden administration did not immediately announce how the doses will be shared or which countries will receive them.

"We need to help fight the disease around the world to keep us safe here at home and to do the right thing of helping other people. It’s the right thing to do; it’s the smart thing to do; it’s the strong thing to do," Biden said in remarks from the White House. 

"We have secured enough supply for all eligible Americans - all Americans 12 years old and older - and we still have work to do, though. Hard work. But because we have done so much here ... we can continue to do more to help the rest of the world," he added.

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