In addition to revising their mask guidelines on Tuesday, the Centers for Disease Control and Prevention also tacitly updated their testing recommendations for people fully vaccinated against the coronavirus.
The agency is now advising to test vaccinated people for the virus if they come into contact with a person with Covid-19, even if they have no symptoms. The health department had previously stated that fully vaccinated people would not need to be tested after exposure to the virus unless they showed symptoms.
“Our updated guide recommends that vaccinated individuals be tested regardless of symptoms of exposure,” said Dr. Rochelle P. Walensky, the agency’s director, in an email to the New York Times. “Tests are available everywhere.”
Fully vaccinated people should wear a mask after exposure in public indoor spaces, the agency said. They should be tested for the virus three to five days later.
If the results are negative, they can stop wearing masks indoors. If the results are positive, the infected person should be isolated at home for 10 days.
While fully vaccinated people can contract the virus, these breakthrough infections are usually mild or asymptomatic. The vaccines approved in the United States offer strong protection against the worst outcomes, including serious illness, hospitalization, and death, including the Delta variant.
The new test recommendation came on the same day that the agency recommended that fully vaccinated people wear masks indoors again under certain circumstances. If the community transmission rate is high, everyone, regardless of vaccination status, should wear masks indoors in public, the agency now says.
The agency also recommended that vaccinated individuals who are in close contact with unvaccinated individuals, including children under the age of 12, consider wearing masks in indoor public spaces regardless of transmission rates in the local community. In one shift, the agency also recommended universal masking in schools.
For months, the CDC had resisted recommending masks to vaccinated people, even as the highly contagious Delta variant spread and the World Health Organization recommended that masks continue to be worn.
The change was prompted by new data suggesting that even vaccinated people infected with Delta can carry large amounts of the virus and spread it to others, said Dr. Walensky at a press conference on Tuesday.
Apoorva Mandavilli contributed to the coverage.