Vaccine Effectiveness of BNT162b2 Against Delta and Omicron Variants in Adolescents.

There are limited data on vaccine effectiveness (VE) against the Omicron variant in adolescents. In Ontario, Canada, most vaccinated adolescents completed their primary series of BNT162b2 during summer 2021; third dose eligibility (6 months following a second dose) expanded to those aged 12-17 years in February 2022. We estimated 2-dose and 3-dose VE against Omicron (BA.1/BA.1.1) and Delta for this age group.