AstraZeneca and Oxford University's COVID-19 vaccine was 79% effective in a large U.S. trial at preventing symptomatic illness, and was 100% effective against severe or critical disease and hospitalization, the drugmaker said on Monday.
The fresh data comes after many countries resuming use of the vaccine after the European Medicines Agency (EMA) and the World Health Organization (WHO) said the benefits outweighed the risks following investigations into reports of blood clots.

