This case-control study compares the effectiveness of Pfizer-BioNTech (BNT162b2) and Covishield (ChAdOx1 nCoV-19) Vaccines against the Alpha and Delta variants.
Both the vaccines showed a rise in its effectiveness after administration of Dose 2.
BNT162b2 has 93.7% and 88%, while ChAdOx1 nCoV-19 shows 74.5% and 67% effectiveness against Alpha and Delta variants, respectively.