All authorized COVID19 vaccines to date are highly effective at preventing severe illness, hospitalization, and death from COVID19. The effectiveness against variant subtypes of COVID19 varies, and is not fully understood. In the clinical trials evaluating the effectiveness of the Pfizer and Moderna vaccines, they were both found to be 95% effective in preventing severe illness, hospitalization, and death. The limited data available indicates that it is likely at least 60% effective against variants such as B.1.1.7.
Is it effective?