Outside of communities seeing “high” levels of COVID-19 transmission, the Centers for Disease Control and Prevention has ended a blanket plea for Americans in hospitals and nursing homes to wear masks indoors.

The change, one of many published Friday evening to the agency’s guidance for COVID-19 infection control for healthcare workers, marks one of the final sets of revisions in a sweeping effort launched in August to overhaul the CDC’s recommendations for the virus.

Since early in the pandemic, the agency had urged “everyone” to wear “source control” like well-fitting masks or respirators while in healthcare settings.

Now, the CDC says facilities in just over a quarter of counties can “choose not to require” all doctors, patients, and visitors to mask.

“Updates were made to reflect the high levels of vaccine-and infection-induced immunity and the availability of effective treatments and prevention tools,” the CDC’s new guidance says.

Originally, the agency made only a narrow set of exceptions for not masking indoors. For example, Americans visiting patients could “choose not to wear source control” if they were all up to date on their vaccines when alone together in a room.

Doctors and nurses who were up to date on their shots could take off their masks when in parts of their hospital not seeing patients, like in a kitchen or staff meeting room.

Instead, after Friday’s revisions, the agency now has exceptions for where masking “remains recommended.” These include situations like during an outbreak among patients, or “when caring for patients who are moderately to severely immunocompromised.”

Holly Harmon, a senior vice president for the American Health Care Association and the National Center for Assisted Living, celebrated the decision in a statement.

“While our commitment to infection prevention and control continues, adapting COVID protocols means recognizing the current stage of this pandemic as well as the importance of quality of life for our nation’s seniors,” Harmon said.

Harmon said the group, which claims to be the largest association representing long-term care facilities, looked forward to its “ongoing collaboration” with the CDC and other public health officials on COVID-19 guidance.

“After more than two years, residents will get to see more of their caregivers’ smiling faces, and our dedicated staff will get a moment to breathe,” Harmon said.

The new guidance comes as the U.S. has recorded a weeks-long slowdown in the pace of COVID-19 hospitalizations and nursing home infections in most parts of the country.

But for now, the CDC says COVID-19 metrics have not improved enough in most communities for hospitals and nursing homes to let up on masking.

The CDC’s guidance for the general public now relies on its “Community Levels” ratings rolled out earlier this year, which factor in levels of hospitalization to come up with weekly ratings. Just 3.5% of Americans now live in counties at “high” “Community Levels,” the CDC says.

In healthcare settings, the CDC says it will still rely on its original “Community Transmission” benchmarks. By this measure of reported cases and test positivity, 73% of counties are currently rated at “high” risk.

“Community Transmission is the metric currently recommended to guide select practices in healthcare settings to allow for earlier intervention, before there is strain on the healthcare system and to better protect the individuals seeking care in these settings,” the CDC says in its guidance.

The CDC also tightened some of its recommendations, reflecting what is now known about the Omicron variant.

One such tweak upends longstanding recommendations not to test most people after a close contact if they have recovered from a previous COVID-19 infection in the last 90 days.

Instead, the CDC says that testing in these situations “should be considered for those who have recovered in the prior 31-90 days.”

A growing body of evidence suggests people can be reinfected by Omicron variant infections within 90 days of recovering.

A report published by the CDC from doctors in France tallied people who were infected as many as three times within months by different strains of the Omicron variant.

“Our findings indicate that the time between confirmed primary infections and reinfections with different Omicron subvariants is frequently shorter than the 90-day definition of reinfections used by the US Centers for Disease Control and Prevention,” the study’s authors wrote before the CDC changed its guidance.