A study posted to bioRxiv reveals that the monovalent XBB.1.5 vaccine booster significantly boosts neutralizing antibodies against new SARS-CoV-2 Omicron sub-variants. The research shows that both XBB.1.5 vaccination and infection elevate neutralizing titers, with the vaccine being particularly effective in infection-naïve individuals and those previously infected with Omicron.
Study compares the effectiveness of bivalent and monovalent booster vaccines against COVID-19 mortality in individuals aged 65 and older. It finds that bivalent boosters show higher vaccine effectiveness against COVID-19 mortality, particularly for the Omicron variant, compared to monovalent vaccines.