CDC Dir. Rochelle Walensky defends new mask guidance for vaccinated Americans, telling @MarthaRaddatz: "We now have science that has really just evolved even in the last two weeks that demonstrates that these vaccines are safe, they are effective." https://t.co/gpjJwNg0q7 pic.twitter.com/0t0SX6OmXN

— This Week (@ThisWeekABC) May 16, 2021