"There's... a glimmer of hope from the recent data that, whilst this variant does still appear to have a significant growth advantage, the magnitude of that advantage seems to have dropped a little bit with the most recent data," Neil Ferguson, an epidemiologist at Imperial College London, told BBC radio.
"There's a good deal of confidence... that vaccines will protect against severe disease... The thing we're slightly concerned about is whether there's an impact on the ability of vaccines to prevent infection or mild disease and therefore prevent transmission in the community."