The CDC eased indoor mask guidance Feb. 25, now relying on how COVID-19 is affecting a community's healthcare system — rather than transmission rates alone — as a guide for mask recommendations.
Under the new framework, an area falls in one of three COVID-19 community levels, with recommended prevention measures varying by level.
"A community's COVID-19 level is determined by a combination of three pieces of information: new hospitalizations for COVID-19, current hospital beds occupied by COVID-19 patients or hospital capacity, and new COVID-19 cases," Greta Massetti, PhD, of the CDC's COVID-19 response incident management team, said during a Feb. 25. News conference.
Here are the COVID-19 community levels, as outlined by the CDC:
Low: This indicates the virus is having a limited effect on the healthcare system, with low levels of severe disease. For counties in this category, the CDC recommends getting vaccinated and boosted, along with testing when sick.
Medium: This means there are more people with severe disease, and communities are beginning to see an increase in how much COVID-19 is affecting their healthcare system. In addition to above measures, the agency recommends people in "medium" level counties who may be at increased risk talk to their healthcare providers about taking additional precautions, such as mask-wearing.
High: At this level, there is a high level of severe disease and high potential for a community's healthcare system to become strained. The CDC recommends everyone in communities at this level wear a mask indoors and in schools, in addition to the precautions at the low and medium levels.
About half of U.S. counties, representing nearly 70 percent of the U.S. population, were in the low or medium COVID-19 community category as of Feb. 25, CDC officials said.
The agency also updated guidance for schools, recommending universal mask-wearing only in schools in communities at the high level. Since July 2021, the agency had previously recommended universal masking in all schools.
"We want to give people a break from things like mask-wearing when our levels are low and then have the ability to reach for them again should things get worse in the future," said CDC director Rochelle Walensky, MD.
"We should all keep in mind that some people may choose to wear a mask based on personal preference," Dr. Walensky said.
The CDC officials also emphasized that people who remain at higher risk for COVID-19, such as people with immunocompromising conditions, may choose to take extra precautions, regardless of their community's COVID-19 level.
"And there are some situations where people should always wear a mask; for example, if they have symptoms, if they tested positive for COVID-19, or if they have been exposed to someone with COVID-19," Dr. Massetti said.
In a statement responding to the updated recommendations, American Medical Association President Gerald Harmon, MD, said, "Millions of people in the U.S. are immunocompromised, more susceptible to severe COVID-19 outcomes, or still too young to be eligible for the vaccine."
"In light of those facts, I personally will continue to wear a mask in most indoor public settings, and I urge all Americans to consider doing the same, especially in places like pharmacies, grocery stores, on public transportation — locations all of us, regardless of vaccination status or risk factors, must visit regularly," Dr. Harmon said.
The CDC's former guidance was based mainly on COVID-19 case counts and recommended people mask up indoors in communities with substantial or high transmission, a category about 98 percent of U.S. counties fell into as of Feb. 23, according to transmission data.