The Pfizer Covid vaccine has received full approval from the FDA. This could pave the way for more vaccine mandates as well as reassure some Americans who are vaccine-hesitant. But we're still learning about the Delta variant—including that fully vaccinated people can still contract and spread the virus. That's part of why the CDC is recommending booster shots for certain groups—and will likely recommend it for everyone later this fall. We unpack boosters, breakthroughs, and Pfizer's FDA approval. And we answer your questions.Want to support 1A? Give to your local public radio station and subscribe to this podcast. Have questions? Find us on Twitter @1A.