AstraZeneca says vaccine 79% effective, no blood clot risk

AstraZeneca's COVID-19 vaccine is 79% effective at preventing the disease and does not increase the risk of blood clots, the biotech firm said Monday, following its U.S. phase III efficiency trials.

The shot was also 80% effective for over 65s, it said. Several countries have advised against administering the jab to older people due to a lack of data among elderly participants in previous trials.