Rising cases of the South African Covid variant in several European countries is "of concern" to the UK, a senior scientific adviser has warned.
Professor Neil Ferguson from Imperial College London said it was vital measures were taken to keep the variant out of the UK.
A group of European countries, including France, are seeing increasing levels of Covid cases, albeit driven by the Kent variantBut there has also been a sharp rise in the number of reported cases of the South African variant, Professor Ferguson said that should strike a note of caution for the UK.
The rising infections meant there needed to be important decisions made on how the UK can trade with France as the country faces a third lockdown, he said.
“Perhaps more concern for the UK though is that some countries are notably seeing a significant fraction, 5-10% of cases, of the South African variant,” Professor Ferguson told BBC Radio 4’s Today programme.
“When infection levels go up in France, 30,000 cases a day, that implies there’s at least 1,500-2,000 cases a day of the South African variant.
“That is the variant we really do want to keep out of the UK.”
Vaccines have been found to struggle more with the South African variant, with between a seven and nine-fold reduction in the level of virus neutralisation involving this variant.Professor Ferguson continued: “I think there are important decisions coming up, and it’s always a balancing act.
“How much we relax the current ban on international travel except for essential services.
“As a lot of essential travel between ourselves and France for business, commerce and trade, how can we reduce the risks associated with that travel.
“Those are policy decisions, I’m just raising the issue that we are doing so well with the vaccination campaign, we are driving down deaths at a faster rate than I ever thought was possible and that will allow us to open up.”
When asked whether he thought France should be added to the red list, he said: “I don’t think that’s necessarily a practical issue given the amount of trade.”
Some regions in France will enter a 'soft' lockdown from midnight on Friday after in a bid to slow rising cases as it faces a third wave of the pandemic.
Three-quarters of new cases are from the more contagious variant that originated in Kent, and more patients who are younger and in better health. All non-essential outlets - except bookshops - will be closed in the Paris region and travel between regions is forbidden without a compelling reason.
But schools will remain open in the region.
The Nice area and, in the north, the Pas de Calais and Dunkirk region, have been in full weekend lockdowns.
People all over France have been under a 6 p.m. to 6 a.m. nationwide curfew for two months. The curfew will now begin an hour later.
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