The Centers for Disease Control and Prevention announced Thursday that those fully vaccinated for COVID-19 can stop wearing masks in most indoor and outdoor settings, though Massachusetts and some other states said they would keep their local restrictions in place for now.
President Biden and federal officials lauded the announcement as a major turning point in the country’s fight against the virus, even as some medical experts questioned its timing and cautioned that masks will remain a part of daily life for some time to come.
“Today is a great day for America,” Biden said during a Rose Garden address heralding the new guidance, an event where he and his staff went without masks.
“If you are fully vaccinated, you no longer need to wear a mask,” he said, summarizing the new advice and encouraging more Americans to roll up their sleeves. “Get vaccinated — or wear a mask until you do.”
The announcement came with US virus cases at their lowest rate since September, deaths from the virus at their lowest since last April, and the test positivity rate at the lowest point since the pandemic began. It has killed more than 584,000 people in the United States, including 17,366 in Massachusetts.
The CDC guidance still calls for wearing masks in crowded indoor settings like buses, planes, hospitals, prisons, and homeless shelters, but it will help clear the way for reopening workplaces, schools, and other venues — even removing the need for social distancing for those who are fully vaccinated.
“We have all longed for this moment — when we can get back to some sense of normalcy,” Dr. Rochelle Walensky, director of the CDC, said at an earlier White House briefing.
The CDC and the Biden administration have faced pressure to ease restrictions on fully vaccinated people — those who are two weeks past their last required COVID-19 vaccine dose — in part to highlight the benefits of getting the shot.
A spokeswoman for Governor Charlie Baker said his administration “welcomes the new CDC guidance and will be updating Massachusetts’ COVID restrictions in the near future. In the meantime, the current mask order remains in place.”
“The Commonwealth is leading the nation in the vaccination effort and the administration will continue to make vaccines available to everyone who lives, works, or studies in Massachusetts,” the spokeswoman, Sarah Finlaw, said in a statement.
Under current rules, Massachusetts residents must cover their faces while in indoor public places and if they are unable to maintain 6 feet of distance from other people while outside.
In Boston, officials “will need an opportunity to review their updated guidance, but in the meantime we will continue to follow the state’s guidance on indoor mask wearing, which is still in effect,” said Nick Martin, a spokesman for Acting Mayor Kim Janey.
Around the United States, some states lifted mask mandates while others took a more cautious approach.
The governors of New York, North Carolina, New Jersey, and Virginia, all Democrats, said they were taking the new CDC guidance under advisement before adopting it. But Illinois, Pennsylvania, Nevada, Connecticut, and Kentucky immediately adjusted their mask wearing guidance, The New York Times reported.
It was unclear Thursday how the new guidance might change policy and practice inside Massachusetts public schools, where teachers and students have been required to wear masks since September. In several districts, including Chelsea and Newton, officials said they will await guidance from state education officials before making any changes.
In Boston, a district spokesman said leaders are reviewing the new guidance and will work with the Boston Public Health Commission to determine what modifications, if any, will be made. In the meantime, the mask requirement will stay in place.
The president of the Boston Teachers Union, Jessica Tang, said she hopes the new guidance will spur more vaccinations.
“From the start of the pandemic, we have been advocating for and following the CDC guidance,” Tang said in a statement. “While we are a bit surprised that the CDC doesn’t consider schools to be ‘indoor crowded spaces,’ we hope that the lifting of these restrictions will incentivize all eligible students, families, and school staff to get vaccinated.”
Infectious disease specialists said the new guidance is based on sound science, but some questioned the timing and wondered how local governments and businesses might enforce mask requirements for some people but not others.
Dr. Joseph G. Allen, an associate professor at Harvard University’s T.H. Chan School of Public Health, applauded the CDC “for taking quick action and updating the guidance based on what is becoming really clear: the vaccines are winning this race against the virus and variants, and our control strategies need to change accordingly.”
Allen said in an interview that it is “absolutely . . . the right time” for the guidance to change, but he acknowledged that it may be happening too quickly for some.
“It’s a confusing time,” he said “We’ve known the playbook for a year, and the playbook feels like it’s shifting, and I recognize that can be uncomfortable to a lot of people, but it is based on sound science.”
But Dr. Nahid Bhadelia, an infectious disease physician and associate professor at the Boston University School of Medicine, is concerned that lifting government mask mandates may be premature in areas with lower vaccination rates and higher infection rates, and she questioned who, if anyone, would enforce a partial mask mandate.
“The trouble . . . is, as a state or a locality, how do you enforce something like this? Because you’re not going to go around checking everybody’s vaccination cards,” said Bhadelia. “So then the question comes up, does it fall on businesses?”
Dr. Ashish K. Jha, dean of the Brown University School of Public Health, questioned whether the nation has reached the threshold at which enough people are vaccinated to make the policy safe.
“I don’t think this is the moment to drop all indoor mask mandates, really for two reasons,” Jha said in an interview. “One is infection numbers are still high. . . And second is, if you’re somebody who became eligible, let’s say in Massachusetts on April 19, to get vaccinated, you’re not finished getting vaccinated yet. . . You may still be waiting for your second shot.”
Jha said he thinks it would be better to wait until early to mid-June, when everyone who wants to get vaccinated has had enough time to do so. There is also the question of protecting children under 12, who are not yet eligible to be vaccinated.
Locally, some parents aren’t ready to have their children stop masking up.
At Corporal Burns Playground in Cambridge, most of the children and all the adults wore masks Thursday.
Bin Yan, 36, said her family has been trying to be careful and does not see other people except when she drops her 2-year-old child off at day care in Cambridge or at the park. She and her toddler keep their masks on outside.
“I think it’s mainly because when we pick him up, the day care still requires masks,” she said. “And if we bring him to the playground, most parents do.”
Until they were fully vaccinated a few weeks ago, the family did not even go to the grocery store, Yan said.
Cyntia Barzelatto, 37, of Cambridge, said she will continue to wear her mask in most indoor settings because of her young children, a toddler and a preschooler.
Barzelatto said she would be comfortable with her children forgoing masks at home and while attending day care in Cambridge, because the community is small and people are tested regularly. Otherwise, when visiting the market or other public indoor settings, she plans to keep her children and herself masked.
“I mean, I’m fully vaccinated, but I don’t know if I would gather with other adults indoors without masks and my kids,” she said. “Maybe with adults only.”
Material from the Associated Press was used in this report. Travis Andersen, Martin Finucane, and Jenna Russell of the Globe staff contributed.