COVID-19: Vaccines giving 67% protection after three weeks, large-scale research shows

One dose of a COVID-19 vaccine gives 67% protection after three weeks, a leading epidemiologist has said. Professor Tim Spector of King's College London, who runs the ZOE COVID-19 surveillance app, said data collected from 50,000 users vaccinated with either the Pfizer or Oxford/AstraZeneca jab showed one dose gave 46% protection after two weeks, rising to 67% after three to six weeks. The app uses information submitted by more than four million users across the world to predict and track coronavirus infections across the UK and other countries