Pfizer’s booster shot is available to persons aged 65 and up, those living in long-term care facilities, as well as people aged 18 to 64 who are at high risk of Covid because of pre-existing medical conditions or their jobs. Pfizer’s initial effort at a booster injection was to ask the FDA to allow the additional doses for anyone aged 16 and up. Last month, the FDA advisory group discussed when to drop booster age requirements, but no decisions were reached.