Understanding what's driving coronavirus mutations

New mutations have seen the virus spread like wildfire in parts of the world. Over a year after the virus was first reported, there are now a large number of strains. Some, like the variants detected in the UK and South Africa, seem to be spreading much faster. Each new infection opens the door to unknown variants which threaten to undo the progress that has been made in the fight against the pandemic. The big question is: will the existing vaccines still work?

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