Professor Chris Whitty said work was being done “urgently” to determine whether the new strain, which is spreading in the south-east of England, could cause a higher mortality rate.
“There is no current evidence to suggest that the new strain causes a higher mortality rate or that it affects vaccines and treatments, although urgent work is being done to confirm this,” he said in a statement.
As with other new variants or strains of Covid-19, it has a genetic footprint that makes it easy to track and happens to be one that is now common. This does not mean that the mutation has made it easier to spread, nor does it necessarily mean that this variation is more dangerous.
Several experts in the genetics and epidemiology of viruses find that it could only be a “lucky” strain that has been amplified due to a spreading event; it could be the mutation that somehow makes it spread more easily without causing more serious illness; or it could just be accidental.
Johnson will hold a news conference on Saturday after meeting with his cabinet on the fastest-growing strain. As cases increase, Johnson may announce additional restrictions.
The government’s scientific advisory group for Covid-19 also warned that the new strain was a “real cause for concern” and called for urgent action. On Twitter, Jeremy Farrar said: “Research is underway to understand more, but urgent action is now essential. There is no part of the UK and the world that is not concerned. As in many countries “The situation is fragile.”
Whitty also asked people to take more precautions. “Given this latest development, it is now more vital than ever for the public to continue to act in their area to reduce transmission,” he said.
Whitty is expected to join Johnson and Patrick Vallance, the government’s chief scientific adviser, at the news conference.