New CDC Guidance Says Fully Vaccinated Teachers and Students Don't Need to Wear Masks Indoors

• The CDC updated its public health guidance for schools Friday, saying fully vaccinated teachers and students don't need to wear masks inside school buildings.
• Teachers and students who are not vaccinated should still continue to wear masks indoors, the U.S. agency said.
• The guidance will likely have no impact on students under 12, who are currently ineligible to get a Covid vaccine in the U.S.

The Centers for Disease Control and Prevention updated its public health guidance for schools Friday, saying fully vaccinated teachers and students don't need to wear masks inside school buildings.

The CDC's new guidance comes about two months after federal health officials permitted the use of the Pfizer-BioNTech Covid vaccine for kids ages 12 to 15, allowing most middle and high school students to get the shots ahead of the fall school semester.

Teachers and students who are not vaccinated should continue to wear masks indoors, the U.S. agency said, adding the practice is especially important when inside and in crowded settings, when social distancing cannot be maintained.

The agency also said it still recommends that students remain at least 3 feet apart in classrooms, combined with indoor mask wearing by people who are not fully vaccinated, to reduce the risk of transmission of the virus.

"When it is not possible to maintain a physical distance of at least 3 feet, such as when schools cannot fully re-open while maintaining these distances, it is especially important to layer multiple other prevention strategies, such as indoor masking," the CDC wrote in its guidance.

The CDC's guidance is only a recommendation, leaving it up to states and local school districts on whether to lift their masking rules for certain people. It will likely have no impact on students under 12, who are currently ineligible to get a Covid vaccine in the U.S.

Covid prevention strategies remain critical to protect people from the virus, especially in areas of moderate-to-high community transmission levels, the agency said.

The updated guidance comes as several states across the U.S. have largely done away with their mask requirements, social distancing and other pandemic-related restrictions because the Covid vaccines have helped drive down the number of new infections and deaths.

In mid-May, the CDC said fully vaccinated people didn't need to wear masks in most settings, whether indoors or outdoors. They are still expected to wear masks on public transportation, the agency said, such as on airplanes, buses and trains. The federal government's mask mandate on public transportation is scheduled to expire on Sept. 13 unless the CDC extends it once again.

The new guidance may be controversial, as scientists and other health experts say indoor mask mandates may make a return this fall, particularly in states with low vaccination rates, as the highly transmissible delta variant spreads across the U.S.

Already the dominant variant in the U.S., delta will hit the states with the lowest vaccination rates the hardest — unless those states and businesses reintroduce mask rules, capacity limits and other public health measures that they've largely rolled back in recent months, experts say.

"I could foresee that in certain parts of the country, there could be a reintroduction of indoor mask mandates, distancing and occupancy limits" in the coming months, said Lawrence Gostin, director of the World Health Organization's Collaborating Center on National and Global Health Law.

Some places, such as Los Angeles County, California, are recommending that "everyone, regardless of vaccination status," wear masks indoors in public places as a precautionary measure.

In Mississippi, where less than a third of the state's eligible population is fully vaccinated, officials last week recommended that all residents continue to wear masks indoors as delta becomes the dominant variant in the state.

In Detroit's public schools, everyone will be required to wear a mask unless everyone in the classroom has been vaccinated. Philadelphia will require all public school students and staff to wear masks inside buildings, even if they have been vaccinated. Masks won't be mandated in Houston schools.

– The Associated Press contributed to this report.