Pfizer wants to expand its COVID-19 booster shots to healthy 5- to 11-year-olds. U.S. health authorities already urge everyone 12 and older to get one booster dose for the best protection. And those 50 and older have the option of a second booster. Pfizer said Thursday new data shows its kid-sized booster could help healthy elementary-aged children rev up virus-fighting antibodies. Pfizer and its partner BioNTech plan to seek authorization of a booster soon. While COVID-19 is a bigger threat to adults, youngsters can get severely ill and omicron caused a surge in child hospitalizations.