Anthony Fauci, describing himself as "very frustrated.".

He said recommending that the vaccinated wear masks is "under active consideration" by the government's leading public health officials.

Also, booster shots may be suggested for people with suppressed immune systems who have been vaccinated, Fauci said.

He noted that some local jurisdictions where infection rates are surging, such as Los Angeles County, are already calling on individuals to wear masks in public regardless of vaccination status.

Fauci said those local rules are compatible with the Centers for Disease Control and Prevention recommendation that the vaccinated do not need to wear masks in public.

"This is an issue predominantly among the unvaccinated, which is the reason why we're out there, practically pleading with the unvaccinated people to go out and get vaccinated," Fauci said.

Fauci said government experts are reviewing early data as they consider whether to recommend that vaccinated individuals to get booster shots

"What I would really like to see is more and more of the leaders in those areas that are not vaccinating to get out and speak out and encourage people to get vaccinated," Fauci said

Anthony Fauci finishes his testimony before the Senate Health, Education, Labor, and Pensions Committee about the status of COVID-19, on Capitol Hill in Washington, Tuesday, July 20, 2021

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