By David Shepardson
WASHINGTON (Reuters) - The Centers for Disease Control and Prevention (CDC) is set on Tuesday to announce revised mask guidance for fully vaccinated Americans in the wake of rising COVID-19 cases and the more transmissible Delta variant, sources said.
Officials told Reuters the CDC is expected to recommend fully vaccinated Americans wear masks indoors in at least some instances, but the specifics are not clear.
The CDC and White House declined to comment. The CDC said it plans a 3 p.m. (1900 GMT) COVID-19 update media briefing.
In May, the CDC advised that fully vaccinated people do not need to wear masks outdoors and can avoid wearing them indoors in most places, guidance the agency said would allow life to begin to return to normal.
The CDC also said in May fully immunized people would not need to physically distance in most places.
CDC Director Rochelle Walensky said in May the new guidance was based on a sharp reduction in cases, expansion of vaccines to younger people, and vaccine efficacy against coronavirus variants.
The CDC in May said it still recommended vaccinated people wear masks on planes and trains, and at airports, transit hubs, mass transit and places like hospitals and doctor's offices.
Top infectious disease official Anthony Fauci said on Sunday on CNN that health officials were considering whether to revise mask guidance for vaccinated Americans, saying it was "under active consideration."