Pfizer COVID-19 vaccine single dose reduces transmission, finds UK Study

After separating the tests from unvaccinated and vaccinated staff, Jones' team found that 0.80% tests from unvaccinated health workers were positive. This compared with 0.37% of tests from staff less than 12 days post- vaccination — when the vaccine's protective effect is not yet fully established — and 0.20% of tests from staff at 12 days or more post-vaccination. The study is yet to be peer-reviewed. This suggests a four-fold decrease in the risk of asymptomatic infection amongst health workers who have been vaccinated for over 12 days, and 75% protection, said Mike Weekes of Cambridge University who also co-led the study.