Understanding low COVID-19 booster uptake among US adults.

Background: Vaccinations against SARS-CoV-2 have consistently been shown to reduce the risk of severe COVID-19 disease. However, uptake of boosters has stalled in the United States at less than 20% of the eligible population. The objective of this study was to assess the reasons for not having obtained a bivalent booster within an existing COVID-19 cohort.