UNC Football Closing In On Herd Immunity Posted Jul 23, 2021 One Atlantic Coast Conference football program not quite at herd immunity is North Carolina. But the Tar Heels are getting close, according to head coach Mack Brown. “We're not at 85 percent for herd immunity with our entire team yet” he said. “We're getting really close.” Could not being at 85 percent affect a team’s ability to play its entire schedule? (Tar Heel Illustrated)