(CN) — Americans living in areas with rising Covid-19 cases should wear face masks indoors in public, even if they're fully vaccinated, the Centers for Disease Control and Prevention recommended Tuesday.
The agency also advised all students, teachers and staff in K-12 schools to wear masks indoors when classes resume in the fall.
A surge in coronavirus infections throughout the country, fueled by lagging vaccination rates and the extremely contagious delta variant, prompted the CDC’s announcement, a reversal from the federal health agency’s position just two months ago.
“The delta variant is showing its willingness to outsmart us,” CDC Director Rochelle Walensky said in a news briefing Tuesday.
Walensky said new data shows “rare occurrences of some vaccinated people infected with the delta variant may be contagious and spread the variant to others.”
She said preliminary research, not yet released, shows vaccinated people who contract the delta variant have the same viral loads as unvaccinated people.
“This new science is worrisome, and unfortunately, warrants an update to our recommendations,” she said.
Despite these “breakthrough” cases, Walensky said coronavirus vaccines are still very effective, reducing the risk of symptoms by seven-fold and hospitalizations 20-fold.
“I think we are still largely in a pandemic of the unvaccinated,” she said. “That’s why we want to double down on people to continue to get vaccinated.”
The new guidance says people in areas with “high” or “substantial” Covid-19 transmission rates should wear masks indoors in public places. The CDC defines high as 50 to 100 cases per 100,000 people and substantial as more than 100 cases. According to agency data, more than 46% of the nation’s counties have high transmission and 17% have substantial transmission.
The CDC continues to recommend all unvaccinated people wear masks, even in areas of low transmission.
Already, some cities and counties across the country have reintroduced face mask mandates.
Los Angeles County reinstated its mask mandate for all people indoors on July 17. Savannah, Georgia, and St. Louis County in Missouri followed suit in recent days.
Missouri Attorney General Eric Schmitt, a Republican, pushed back against the measure and filed a lawsuit late Monday seeking to overturn the rules.
“This continued government overreach is unacceptable and unconstitutional, especially in the face of a widely available vaccine,” Schmitt said in a statement. “There is absolutely no scientific reason to continue to force children to wear a mask in school.”
Florida Governor Ron DeSantis has signaled he might call a special legislative session to ban mask mandates in public schools.
“There is no evidence in places … they didn’t have masks, they had these horrible outcomes,” the Republican governor said during a roundtable Monday.
The CDC director stopped short of recommending employers require workers to become vaccinated because that directive would be beyond the agency’s authority, but some government leaders have already imposed such rules.
The U.S. Department of Veterans Affairs announced mandatory Covid-19 vaccines for personnel, following four VA employees’ deaths in the last few weeks.
California will require all state employees as well as public and private health care workers to receive a vaccination or submit to weekly testing. New York City will also require vaccinations or testing for all municipal workers.
The latest CDC guidance walks back its May recommendation that vaccinated Americans could stop wearing masks in most places. Since then, the delta variant has become the dominant coronavirus strain and more than a third of Americans remain unvaccinated.
“This is not a decision we have made lightly,” Walensky said. “I know we’re 18 months into this pandemic and people are tired … This is not a welcome piece of news that masking is going to be part of the lives of those who are vaccinated.”
Following the CDC briefing, President Joe Biden said he will announce new measures to promote vaccinations on Thursday.
“By following the science, and by doing our part by getting vaccinated, America can beat Covid,” he said in a statement. “In the meantime, more vaccinations and mask wearing in the areas most impacted by the delta variant will enable us to avoid the kind of lockdowns, shutdowns, school closures, and disruptions we faced in 2020 …We are not going back to that.”
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