Centers for Disease Control and Prevention director Rochelle Walensky told "Fox News Sunday" that political pressure had nothing to do with the agency's sudden announcement that fully vaccinated Americans can go without masks in most indoor settings.

Why it matters: Emerging evidence shows vaccinated people are less likely to transmit the virus, as COVID-19 cases and deaths drop. But the responsibility to uphold the abrupt policy change falls to individuals and businesses.

What she's saying: "I can tell you it certainly would have been easier if the science had evolved a week earlier and I didn't have to go to Congress making those statements, but I'm delivering the science as the science is delivered to the medical journals," Walensky told Fox News' Chris Wallace.

• The agency's guidance change came just days after Walensky, during a Senate hearing Tuesday, defended the CDC's guidelines at the time telling all Americans to wear masks.

State of play: "This was not permission to shed masks for everybody, everywhere," she told NBC's Meet the Press. "This was really science-driven individual assessment of your risk."

• "If they are vaccinated and they are not wearing a mask, they are safe. If they are not vaccinated and they are not wearing a mask, they are not safe."
• "We're not counting on vaccine mandates at all. It may very well be that local, local businesses, local jurisdictions will work towards vaccine mandates. That is going to be locally driven and not federally driven," Walensky said.

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