A combination of new coronavirus variants and increasing vaccine hesitancy means that despite a strong vaccine rollout, the U.S. won’t likely reach herd immunity any time soon, The New York Times reports. More than half of all American adults have received at least one dose of an anti-COVID-19 vaccine, but the number of people signing up for their second dose or to be inoculated at all is waning, according to latest data. The Biden administration’s top adviser, Dr. Anthony Fauci, has admitted that the promise of herd immunity now seems a far reach but the infections will eventually go down. “People were getting confused and thinking you’re never going to get the infections down until you reach this mystical level of herd immunity, whatever that number is,” he said, according to the Times.“That’s why we stopped using herd immunity in the classic sense. I’m saying: Forget that for a second. You vaccinate enough people, the infections are going to go down.”