Emerging variants of SARS-CoV-2 raise concerns about vaccine efficiency. Here, the authors present a post-hoc analysis for the ChAdOx1 nCoV-19 (AZD1222) vaccine trial in Brazil and provide efficacy against symptomatic COVID-19 caused by the Zeta (P.2) and other variants.
- Sue Ann Costa Clemens
- Pedro M. Folegatti
- Rafael Zimmer