Real-world evidence for effectiveness of vaccination against 4 SARS-CoV-2 VOCs in Canada

Toronto-based researchers recently conducted a study to determine the effectiveness of BNT162b2 (Pfizer-BioNTech), mRNA-1273 (Moderna), and ChAdOx1 (AstraZeneca) vaccines against symptomatic COVID-19 infection caused by the Alpha, Beta, Gamma, and Delta variants between December 2020 to May 2021.