How effective has the bivalent booster COVID vaccination been?

In a recent study published in the journal Eurosurveillance, researchers estimated the effectiveness of bivalent messenger ribonucleic acid (mRNA) vaccines targeting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron BA.1 subvariant and the original Wuhan-Hu1 strain against Omicron infections in the vaccinated population of the Netherlands between 26 September and 19 December 2022.