Sofia MoutinhoScience’s COVID-19 reporting is supported by the Heising-Simons Foundation.As potentially more dangerous coronavirus variants spread worldwide, scientists and clinicians have raced to discover how well the available COVID-19 vaccines protect against the mutant strains.
Preliminary results from a large study of health care workers now suggest one dose of CoronaVac, a vaccine developed by a Chinese company, is still about 50% effective against symptomatic COVID-19 in a Brazilian city where more than three-fourths of new cases are caused by the highly transmissible variant known as P.1.That real-world protection is about the same level clinical trials saw with two doses of CoronaVac against the standard, or “wild type,” pandemic.