President Biden received his COVID-19 vaccine booster shot on Monday, after public health officials recommended boosters for many Americans, including those 65 and older. Mr. Biden, 78, got his third shot on camera, and delivered brief remarks before his jab. The Food and Drug Administration granted an emergency use authorization last week for booster doses of Pfizer’s COVID-19 vaccine six months after the completion of the two-dose course for those 65 and older, those with some underlying conditions and those who work in high-risk environments. The Centers for Disease Control and Prevention also recommended a booster shot for these groups...