Researchers examine effectiveness of Pfizer vaccine against COVID-19
A major study, conducted in collaboration with researchers from Harvard University, examined data on 600,000 vaccinated individuals in Israel, along with 600,000 matched unvaccinated controls.
Two doses of Pfizer/BioNTech vaccine reduced symptomatic COVID-19 by 94% and severe disease by 92%; Single-dose reduced symptomatic COVID-19 by 57% and severe disease by 62%; Vaccine effectiveness was found to be similar across age groups; B.1.1.7 variant became dominant in Israel during the study period.
The Clalit Research Institute, in collaboration with researchers from Harvard University, analyzed one of the world's largest integrated health record databases to examine the effectiveness of the Pfizer vaccine against COVID-19.