What happened with the AstraZeneca vaccine?

Available for over a year

Some of the European Union's biggest nations have restarted their roll-out of the Oxford-AstraZeneca vaccine after the medicines regulator concluded it was safe and effective. Ros Atkins considers how a vaccine initially hailed as a "gamechanger", has ended up in the middle of a scientific and political storm. (Photo: A medical worker holds a vial of theAstraZeneca Covid-19 vaccine at a school gym in Tirana. Credit: Gent Shkullaku/Getty)