Instead of the bivalent COVID-19 vaccines comprising both the original and omicron BA.4/BA.5 SARS-CoV-2 strains that have been in use in the U.S. since April, the CDC’s Advisory Committee for Immunization Practices voted 13-1 Sept. 12 to recommend the universal use of updated monovalent XBB-containing COVID-19 vaccines as authorized or approved by the FDA.