Don’t panic, AstraZeneca vaccine is still good

Health officials around the world gave their backing to the AstraZeneca vaccine against Covid-19, after a study showing it had little effect against mild disease caused by the variant now spreading quickly in South Africa rang global alarm.

The prospect that new virus variants could evolve the ability to elude vaccines is one of the main risks hanging over the global strategy to emerge from the pandemic by rolling out vaccines this year.