New Delhi: The United Kingdom’s Department of Health and Social Care called for an emergency meeting of its joint monitoring group Monday in view of a new strain of coronavirus that is fast spreading in London and southeast England.
In London, 62 per cent of infections reported in the second week of December were due to the new strain, compared to 28 per cent three weeks earlier.
The new strain, dubbed VUI-202012/01 (first variant under investigation in December 2020), is said to be 70 per cent more infectious and Health Secretary Matt Hancock said Sunday that it “was out of control”.
The latest data identified additional sequences in S:501 mutant variants from the UK, Denmark, Australia, & South Africa, but no additional countries.
(!This table does not distinguish variants & some countries listed haven't seen 501 in months!)
— Dr Emma Hodcroft (@firefoxx66) December 20, 2020
Saturday, UK Prime Minister Boris Johnson announced a “stay at home” order in London and southeast England due to concerns over the new strain, crushing hopes that Covid-19 restrictions would be eased over Christmas. The UK reported a record daily rise in Covid-19 cases Sunday with 35,928 new infections.
Ireland, Germany, France, Italy, the Netherlands, Turkey, Belgium and Switzerland have temporarily halted passenger flights to and from the UK due to fears over the new strain. The Netherlands was the first to initiate a ban after Dutch authorities said they found at least one case of the variant virus.
However, experts say that the greater transmissibility is based on modelling the spread of the disease, not laboratory experiments. Additionally, there is also no evidence to indicate that the mutation causes a more severe disease or is resistant to any of the existing vaccine candidates.
Previous mutations of SARS-CoV-2 have expectedly and unsurprisingly appeared in multiple countries since the pandemic began, as viruses mutate regularly when they replicate. In November, Denmark controversially culled up to 17 million mink found to have been transmitting a mutant strain of Covid-19.
How did the new variant emerge?
The new strain was discovered by Public Health England’s genomic surveillance. The agency notified the UK government on 18 December on the seriousness of the new strain, and the UK submitted its findings to the World Health Organization the same day.
The new UK variant is believed to have first emerged in southeast England in September. It has since become the dominant form of the virus in the area. It has also been found in Denmark, The Netherlands, and Belgium.
According to Patrick Vallance, the UK’s Chief Scientific Adviser, the new strain may be in other countries as well, but might have started in the UK, adding that “it’s leading inevitably to a sharp increase in hospital admissions”.
The strain is a derivative of the D614G mutation, which appeared independently in multiple locations. However, only one lineage of that mutation spread rapidly across the globe, driven by human behaviour, according to virologists, and is now found in nearly all sequences.
Yes – almost all SARS-CoV-2 circulating now has the D614G mutation. From our global build, I've coloured sequences by the 614 position. You can see how 'G' has come to dominate. So the mutations in new variants are in what we call a '614G background'.https://t.co/g3rnt6jBph pic.twitter.com/iWfJ9XU9Gt
— Dr Emma Hodcroft (@firefoxx66) December 19, 2020
The mutation did not show any indication of increased virulence or ability to spread.
The new variant has appeared independently in the UK and South Africa, and experts say this is not unusual as viruses undergo numerous mutations. The South African variant clade is now called 501Y.V2.
What are the latest scientific findings?
The new Covid-19 strain can be identified through current swab tests, UK’s Chief Medical Officer Chris Whitty has said. It is currently being reviewed by the country’s top scientists.
Dr Ravi Gupta, professor of Clinical Microbiology at the University of Cambridge, and other researchers have posted a preliminary report about developments on the new variant, but this is yet to be peer-reviewed.
The new variant contains 23 genetic changes, several due to alterations in a protein made by the virus. According to Prof. Nick Loman from the Covid-19 Genomics UK (COG-UK) Consortium, this is a “surprisingly large number of mutations” and “more than we would expect”.
In both the variants from the UK and South Africa, two notable mutations have been found in the crucial spike protein that allows the virus to enter human cells and hijack them. These are the mutation N501Y, where the amino acid N mutates to Y at the 501st position in the sequence, and the H69/V70 deletion, where two amino acids in the spike protein are deleted.
The 69-70 deletion was previously found in the now-culled Danish minks, and was also seen in an immune-suppressed patient who became resistant to convalescent plasma. Viruses are known to mutate vigorously in immunocompromised patients with prolonged illnesses.
The deletion arose independently in Thailand and Germany earlier this year as well.
The N501Y mutation was first observed in Brazil in April but remained at low frequency until now. Virologists are still investigating the possibilities of other mutations in the two strains now in UK and South Africa, which could affect transmissibility.
Will the variants be resistant to current vaccine candidates?
The possibility that the new variants will be resistant to existing vaccine candidates is low, but not “inexistent”, Dr Moncef Slaoui, chief science adviser for the US government’s vaccine distribution effort, said Sunday.
Other researchers also say the mutations are not expected to be resistant to existing vaccine candidates, which will still protect against them. Unlike influenza viruses, the coronavirus evolves and mutates at a much slower rate.
However, as more and more people get vaccinated, researchers expect the virus to evolve mutations that will help make it resistant to vaccines in the future.