AstraZeneca said Thursday its COVID-19 vaccine is 76 percent effective at preventing symptomatic illness and completely effective at preventing severe or critical forms of the disease, according to a new analysis of updated results from its U.S. trial.

Earlier in the week, the drugmaker said the shot was 79 percent effective, but the U.S. National Institute of Allergy and Infectious Diseases accused the company of including outdated information. 

(With input from Reuters)