Two cases of another new strain of COVID-19 linked to South Africa have been identified in the UK, Matt Hancock said.
Speaking at a Downing Street press conference on Wednesday, the health secretary said the second new variant “is yet more transmissible and it appears to have mutated further” than the one previously identified in the UK.
He said: “Both cases are contacts of cases who have travelled from South Africa over the past few weeks.
“The chief scientific adviser and the chief medical adviser and others met their South African counterparts over the last day, and we are incredibly grateful to the South African government for the rigour of their science and the openness and the transparency with which they have rightly acted, as we did when we discovered a new variant here.
“This new variant is highly concerning because it is yet more transmissible and it appears to have mutated further than the new variant that has been discovered in the UK.”
Watch: Matt Hancock announces further Tier 4 restrictions
Hancock said both cases and close contacts of the cases have been quarantined.
There are immediate restrictions on travel from South Africa and those who have been in contact with anyone who has been in South Africa in the last fortnight must quarantine.
He added: “These measures are temporary while we investigate further this new strain, which is shortly to be analysed at Porton Down.”
Latest figures suggest the South African strain was behind a record number of people being hospitalised in the country.
Hancock also announced that millions more people in England will soon be subject to the most severe Tier 4 restrictions.
On Boxing Day, Sussex; Oxfordshire; Suffolk; Norfolk; Cambridgeshire, parts of Essex not yet in Tier 4; Waverley in Surrey; and Hampshire including Portsmouth and Southhampton but excluding the New Forest will all join Tier 4.
Hancock said: “I know these actions have consequences. I know how difficult it is. But I also know that it is right to take the action that is necessary to control this virus.”
Boris Johnson introduced Tier 4 on Saturday, initially for parts of London, South East and the East of England.
Anyone in a Tier 4 area must not mix with people outside their household.
Non-essential shops, gyms, cinemas, hairdressers and bowling alleys have to close and people are also be restricted to meeting just one other person from another household in an outdoor public space.
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