All coverage
Brazil researchers now say China's Sinovac vaccine is 50% effective — lower than announced earlier
By Nee Lee & Yen Nee Lee
Pfizer, BioNTech Boost Vaccine Output Goal by More Than 50%
By Riley Griffin & Naomi Kresge
Doctor's Death After Getting the Covid-19 Vaccine Is Investigated
By Denise Grady & Patricia Mazzei
Sinovac: Brazil results show Chinese vaccine 50.4% effective
By Philippa Roxby