CDC updates guidance, recommends vaccinated people wear masks indoors in certain areas - CNN

"This is not a decision that we or CDC has made lightly."

New unpublished data showing that vaccinated people infected with the Delta coronavirus variant can have as much virus as those who are unvaccinated is the primary driver for the CDC's latest mask guidance change, a source involved with the decision process told CNN.

The White House is hoping that the new guidance will give local officials "a lot of cover" to implement new mask mandates where appropriate.

Meanwhile, the guidance for unvaccinated people remains the same: continue masking until they are fully vaccinated.

Nearly half -- 46% -- of US counties currently have high transmission and 17% have "substantial" transmission, according to data from the CDC, as of Tuesday morning.

In two states, Arkansas and Louisiana, every county is currently listed as having "high" levels of community transmission of Covid-19, according to CDC data.

"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."

The CDC's latest guidance also recommends for community leaders to encourage vaccination and mask-wearing to prevent further outbreaks in areas of substantial and high transmission.

Earlier this month, the CDC's Covid-19 school guidance noted that fully vaccinated people do not need to wear masks, and then about a week later the American Academy of Pediatrics issued stricter guidance recommending that everyone older than 2 wear a mask in schools, regardless of vaccination their status.

"But clearly, if you want to protect your children under 12 or grandchildren, or protect immunocompromised people, as well as protect your own health -- from even mild disease -- then you should be wearing a mask, particularly in areas of high transmission when indoors."

Guidance has been in talks for days

The last time the CDC updated its mask guidance was two months ago, to say most people who are fully vaccinated could go without masks indoors.

That guidance moved so quickly that administration officials were informed less than a day before -- and many public health experts were taken by surprise.

This time, the CDC's updated guidance has been expected for some days now.

As the highly contagious Delta coronavirus variant continues to circulate across the United States, top federal health officials debated whether to issue new guidance on masks, huddling on Sunday night to go over the new data and evidence regarding the transmissibility of the variant and breakthrough cases among vaccinated people, according to a person familiar with the talks.