The UK has toughened COVID-19 restrictions after a highly infectious new strain of the virus was discovered.
Speaking during a Downing Street press conference, the prime minister announced the festive bubble policy across Tier 1, 2 and 3 areas of England would be scaled back to just Christmas Day.
He also said London and areas in the South-East would be placed in a stricter Tier 4 system and be banned from mixing at Christmas in a bid to prevent a new variant of coronavirus from spreading.
Scotland and Wales have also announced a tightening of restrictions amid the rising cases.
Here are four things we learned today about the new strain of coronavirus
The new strain is up to 70 per cent more transmittable
The new variant coronavirus can spread more rapidly, England’s chief medical officer, Professor Chris Whitty, said during a Downing Street press conference on Saturday.
The government’s chief scientific adviser, Sir Patrick Vallance added the new strain, which was thought to have emerged in mid-September in London or Kent, had a “significant substantial increase in transmissibility”.
It may be up to 70% more transmissible than the old variant.
Sir Patrick said by December over 60% of infections in the capital had been the new variant, adding: “It moves fast”.
There is no evidence vaccine less effective against new strain
Health Secretary Matt Hancock has said it is highly unlikely the mutation will fail to respond to a vaccine.
However, Sir Patrick warned the new variant was becoming the dominant strain, with a rapid rise in cases in recent days.
Dr Jeremy Farrar, Director of Wellcome, added: “However, the mutation is a reminder of the power of the virus to adapt, and that cannot be ruled out in the future. Acting urgently to reduce transmission is critical.
“Difficult as this year has already been, we must stay humble. There are still many unknowns about Covid-19 and it remains a grave threat to us all.”
Watch: PM says residents in Tier 4 must stay home
There is no evidence new strain more lethal
Prof Whitty has said there is no current evidence to suggest the new strain causes a higher mortality rate or affects treatments.
But he added, “urgent work” was underway to confirm this and warned it was “more vital than ever” people continued to take action to reduce the spread of the virus.
Sir Patrick said: “There’s no evidence it causes a more severe disease, causes more hospitalisation, causes more trouble than the other virus.
“So it basically looks similar.”
New strain could increase R rate by 0.4
It was revealed early analysis showed the new strain could increase the COVID-19 reproductive rate by 0.4 or more.
Sir Patrick said: “This virus spreads more easily and therefore more measures are needed to keep it under control.
“We absolutely need to stick to the basics of making sure that we reduce our contacts, reduce the ability for this virus to spread, and that’s the reason that tougher measures are required to keep their variant under control.”
Prof Peter Openshaw, past-President of the British Society for Immunology and Professor of Experimental Medicine at Imperial College London, added: “The information that the government has just issued about this new variant coronavirus is of great concern.
“The doubling time is now at just 6 or 7 days so it is really vital that we get this under control.”
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