On Tuesday, the Centers for Disease Control and Prevention reversed its guidelines for vaccinated Americans. Now, the CDC says that vaccinated Americans should wear face coverings indoors to help protect against the delta variant. This is a  quick turnaround from May when the CDC finally updated its guidelines for vaccinated Americans.

The Centers for Disease Control and Prevention recommended Tuesday that fully vaccinated people begin wearing masks indoors again in places with high Covid-19 transmission rates. The agency is also recommending kids wear masks in schools this fall.

Federal health officials still believe fully vaccinated individuals represent a very small amount of transmission. Still, some vaccinated people could be carrying higher levels of the virus than previously understood and potentially transmit it to others.

“This pandemic continues to pose a serious threat to the health of all Americans,” CDC Director Rochelle Walensky told reporters on a call. “Today, we have new science related to the delta variant that requires us to update the guidance regarding what you can do when you are fully vaccinated.”

“In areas with substantial and high transmission, CDC recommends fully vaccinated people wear masks in public, indoor settings to help prevent the spread of the delta variant, and protect others. This includes schools,” Walensky said. The CDC recommends that everyone in grade schools wear masks indoors, “including teachers, staff, students and visitors, regardless of vaccination status.”

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