In a report released on December 2, 2022, the Centers for Disease Control and Prevention (CDC) shared research findings related to bivalent and monovalent COVID-19 vaccines. According to the report, CDC research shows that monovalent mRNA COVID-19 vaccines were less effective at protecting against COVID-19 considering the widespread dominance of the omicron variant. The report showed that individuals who got a bivalent booster in addition to their primary monovalent vaccine series were significantly better protected against COVID-19 than those who had not received a bivalent booster.
For the best protection against COVID-19, the CDC encourages everyone to stay up to date on recommended COVID-19 vaccines and for eligible people to get a bivalent booster.
Access the CDC report here: Effectiveness of Bivalent mRNA Vaccines in Preventing Symptomatic SARS-CoV-2 Infection — Increasing Community Access to Testing Program, United States, September–November 2022