Editor's note, 23 December 2020: This article was updated with the latest information.
Scientists are now confident that a new variant of the SARS-CoV-2 virus is more contagious but say studies are underway to test its impact on containing COVID-19
What is different about this variant?
The new variant of the SARS-CoV-2 virus, known as VUI-202012/01, or lineage B.1.1.7, carries an unusually large number of mutations.
Three of the mutations have potential biological effects. These have been identified as:
- Mutation N501Y – one of six key contact residues within the receptor-binding domain that can increase binding affinity to human and murine ACE2.
- The spike deletion 69-70del that affects the capacity to evade human immune response
- Mutation P681H adjacent to the furin cleavage site
How was it identified?
The variant was identified by Public Health England monitoring, following a surge in cases seen in Kent and London.
The two earliest sampled genomes belonging to B.1.1.7 lineage were collected on 20 September in Kent, followed by another on 21 September in Greater London.
How widespread is it?
According to the COVID-19 Genomics Consortium UK (COG-UK), as of 15 December, there were 1623 genomes in the B.1.1.7 lineage.
Of these 519 were sampled in Greater London, 555 in Kent, 545 in other regions of the UK including both Scotland and Wales, and four in other countries.
Is it more contagious?
Genomic data suggests a growth rate of the new virus variant 71% higher (95% confidence level: 67% - 75%) than other variants.
Although it remains too early to say with certainty that the variant is responsible for increased numbers of cases, the New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG) said on 18 December that the variant had "demonstrated exponential growth during a period when national lockdown measures were in place".
The panel concluded that that VUI-202012/01 "demonstrates a substantial increase in transmissibility compared to other variants".
Is the new variant more dangerous?
Sharon Peacock, executive director of COG-UK, told a briefing hosted by the Science Media Centre yesterday: "We have no evidence that there is an association with a worse outcome."
Prof Tom Connor, reader at the School of Biosciences, Cardiff University, said it was too early to be sure, as outcomes were determined after 28 days following diagnosis. "We're not at that point where you'd have that outcome information to do that analysis yet," he told the briefing.
Public Health England has said: "We currently have no evidence that the variant is more likely to cause severe disease or mortality – but we are continuing investigations to understand this better."
Is the UK alone in being identified with the variant?
Experts have suggested that UK science might be just better at identifying variant strains of the virus than most other countries.
According to Prof Connor, "It is probable that similar variants are popping up around the world.
"We are sequencing in the UK at a disproportionate rate to other people, which means that we have a much better system for catching this," he told the briefing.
Is there any evidence that children are spreaders now?
At a news conference this week, Boris Johnson evaded a commitment that all children would be back at school at the start of January, reflecting suggestions that school-age children might be spreading the virus.
Experts today said that there was no evidence this was the case.
However, Judith Breuer, professor of virology and co-director of the Division of Infection and Immunity at University College London said: "We know that coronavirus is spread very easily amongst children, so it wouldn't surprise me if eventually the SARS-CoV-2 virus ended up spreading amongst children."
Will the new variant be resistant to current vaccines?
There is no current evidence that the new variant of SARS-CoV-2 will be resistant to COVID-19 vaccines.
PHE said this week that laboratory work was currently being undertaken as a priority to understand this.
Professor Ravi Gupta, professor of clinical microbiology at the University of Cambridge said that "the new variant is very unlikely to escape vaccines because vaccines elicit T-cell responses, antibody responses, and both of those responses are targeting multiple parts of the spike".
Ugur Sahin from BioNTech, whose COVID-19 vaccine was the first to be approved for emergency use worldwide, and in the UK, said he was confident the company's vaccine would remain effective against the new variant.
However, he acknowledged that more research was needed before he could confirm the efficacy.
Was this new variant unexpected?
It is not uncommon for viruses to undergo mutations; seasonal influenza mutates every year. Variants of SARS-CoV-2 have been observed in other countries, such as Spain.
Prof Tom Solomon, director of the NIHR Health Protection Research Unit in Emerging and Zoonotic Infections, at the University of Liverpool, said: "SARS-CoV-2, the virus which causes COVID-19, is evolving and mutating all the time, as do all similar viruses. Such changes are completely to be expected."
Dr Jeremy Farrar, director of the Wellcome Trust, said the latest development showed there would still be surprises from SARS-CoV-2. "We have to remain humble and be prepared to adapt and respond to new and continued challenges as we move into 2021," he said.