AstraZeneca Covid Vaccine 100% Effective Against Hospitalizations and Deaths, Per Final-Stage U.S. Testing Posted byKenny Herzog March 22, 2021 Leave a comment on AstraZeneca Covid Vaccine 100% Effective Against Hospitalizations and Deaths, Per Final-Stage U.S. Testing The UK-based pharmaceutical maker’s two-shot solution appears to be even more efficacious against symptomatic infection than Johnson & Johnson’s one-dose injection.