Researchers who scoured the records of nearly 800,000 U.S. veterans found that in early March, just as the Delta variant was gaining a toehold across American communities, the three vaccines were roughly equal in their ability to prevent infections.
But over the next six months, that changed dramatically.
By the end of September, Moderna’s two-dose COVID-19 vaccine, measured as 89% effective in March, was only 58% effective.
Oakland Public Health Institute
Browse the articles related to this topic below.
Join our community on Guilded.