Video report by ITV News Senior Correspondent Paul Davies
Professor Wendy Barclay, head of G2P-UK National Virology Consortium, a new project set up to study the effects of emerging coronavirus mutations, said one Brazilian variant of coronavirus has been detected in the UK.
She said: “There are two different types of Brazilian variants and one of them has been detected and one of them has not.”
Professor Barclay noted the variant detected in the UK was not the one that was causing concern for the government.
She said: "The new Brazilian variant of concern, that was picked up in travellers going to Japan, has not been detected in the UK."
She added: “In the databases, if you search the sequences, you will see that there is some evidence for variants from around the world, and I believe including the Brazilian one, which probably was introduced some time ago.
“And that will be being traced very carefully.”
Yesterday the UK banned travellers from South America over concerns about the new strains that have originated from Brazil.
ITV News Science Editor Tom Clarke on how worried we should be about the Brazil variant
Scientists analysing the Brazilian variant believe the mutations it shares with the new South African strain seem to be associated with a rapid increase in cases in locations where there have already been large outbreaks of the disease.
Transport Secretary Grant Shapps told ITV News the ban was "belt and braces thing", to ensure the vaccination programme rolling out across the UK was not disrupted by new variants of the virus.
He said there was no evidence the strains from Brazil were immune to the vaccines.
The government's chief scientific adviser Sir Patrick Vallance told ITV on Wednesday there was "no evidence" any of the newly discovered variants of Covid-19 caused a more severe illness.
Epidemiologist Dr Mike Tildesle said the new “more transmissible” coronavirus variant found in Brazil was “first detected in travellers going to Tokyo” before it was traced back to South America.
Speaking to the BBC, he said although scientists “don’t believe there is anything to worry about” in terms of vaccine efficacy, the higher transmissibility could mean “people potentially might end up developing severe symptoms more rapidly which could cause more issues with our health service”.
Brazil passed 200,000 deaths from the pandemic earlier this week, the second highest total around the globe.