Since the early days of the pandemic, scientists have been tracking changes in the genetic code of the coronavirus.
All viruses naturally mutate, and Sars-CoV-2 is no exception, accumulating an estimated one or two changes a month.
Mutations are generally a chance event that will have little impact on the properties of a virus.
Most are merely “passengers”, says Dr Lucy van Dorp, an expert in the evolution of pathogens at University College London (UCL).
“Mutations are in fact rarely a bad thing,” she explains.
“The very vast majority of mutations which we observe in genomes of Sars-CoV-2 are there as passengers.
“They don’t change the behaviour of the virus, they are just carried along.”