food and drug administration has authorized the pfizer booster for people ages 16 and 17. so 16 and 17-year-olds who got the pfizer vaccine to begin with, six months after their second shot, they would then be eligible to get a booster with pfizer. let s take a look at some numbers. once this goes through, 2.6 million u.s. teens will be eligible for a booster. already 141 million adults are eligible. now, for adults, they can do a mix and matcha approach to boosters, get a different booster shot than the shots that they got initially. but for 16 and 17-year-olds who got pfizer, they do need to get pfizer as their booster. christine, laura? all right, elizabeth, thank you for that. it is time for three questions in three minutes. so let s bring in dr. ali raja, professor of emergency medicine at harvard medical school and vice chair of emergency medicine at mass general ral. doctor, so nice to have you. so, the fda and cdc both now