The head of the Centers for Disease Control and Prevention told Congress that a widely-available vaccine probably won't be available until well into 2021. But he did say that masks are perhaps even more useful in preventing the spread. That will prove especially true if people are reluctant to take the vaccine.This episode: White House reporter Ayesha Rascoe, congressional reporter Claudia Grisales, and science correspondent Joe Palca.Connect:Subscribe to the NPR Politics Podcast here.Email the show at nprpolitics@npr.org.Join the NPR Politics Podcast Facebook Group.Listen to our playlist The NPR Politics Daily Workout.Subscribe to the NPR Politics Newsletter.Find and support your local public radio station.