Deborah Sampson, left, a nurse at a University of Washington Medical Center clinic in Seattle, gives a Pfizer COVID-19 vaccine shot to a 20-month-old child, June 21, 2022, in Seattle. Pfizer is asking U.S. regulators to authorize its updated COVID-19 vaccine for children under age 5. The youngest tots already are supposed to get three extra-small doses of the original vaccine as their primary series. Pfizer and its partner BioNTech said Monday, Dec. 5, 2022 that if the Food and Drug Administration agrees, the updated vaccine would be used for the third shot. The FDA already has cleared COVID-19 vaccines tweaked to better target omicron as boosters for everyone 5 and older. (AP Photo/Ted S. Warren, file)
