This study investigates the effectiveness of COVID-19 vaccine boosters following a primary series of CoronaVac vaccination. Using data from Brazil during the Omicron wave, the authors show that boosters provided protection against severe disease, with higher effectiveness from a BNT162b2 than CoronaVac booster.
- Otavio T. Ranzani
- Matt D. T. Hitchings
- Julio Croda
