AstraZeneca PLC and Moderna, Inc. both announced that their COVID-19 vaccines show signs of efficacy against the Delta (B.1.617.2) and other SARS-CoV-2 variants of concern as evidence mounts that Delta in particular is able to evade protection by Moderna’s mRNA-1273 and Pfizer Inc./BioNTech SE’s BNT162b2. The question now is whether booster shots will provide protection from the variant, first identified in India, as well as other more virulent strains.
London-based AstraZeneca said on 28 June that an analysis from the University of Oxford-led COV001 and COV002 trials of Vaxzevria,...








