Pharmacies across the U.S. have started administering new COVID-19 booster formulations from drugmakers Pfizer and Moderna.

The Food and Drug Administration approved the revised mRNA vaccine shots Monday as several COVID variants spread and hospitalizations rise. The Centers for Disease Control and Prevention recommends the shots for everyone 6 months and older. The vaccine is similar to previously approved formulas but it was updated to target the XBB variants that became prevalent last winter.