With caution, but without panic
A new strain of coronavirus has appeared in the UK. Presumably, it is 71% more contagious
Maria Azarova, Naked Science
In the county of Kent in the south-east of the UK, where there has recently been a surge in the incidence of Covid-19, a new strain of coronavirus has been recorded. He was even given a personal name – VUI – 202012/01 (or line B.1.1.7). Yesterday, Prime Minister Boris Johnson announced stricter isolation measures, saying that a new version of the virus appears to be spreading faster.
At a press conference last Saturday, the chief scientific adviser to the British government, Patrick Vallance, said that VUI - 202012/01 accounted for about 26% of cases of infection by mid–November. "By December 9, these figures were much higher. – In London, more than 60% of all cases were accounted for by the new option," he said.
In fact, the first cases of infection with VUI – 202012/01 occurred back in September, by December 13, 1108 people had already been infected with it in the UK, and by the 15th, more than 1.6 thousand. The real number is likely much higher. According to experts, there is no data suggesting that a new version of the virus was "imported" from abroad. Therefore, apparently, it originated in the United Kingdom.
This news forced many residents of the British capital to leave the city even before the new restrictions came into force, which eventually led to overcrowding of railway stations. Soon, about 30 countries announced the suspension of air traffic with the UK, among them – the states of the European Union, Morocco, Kuwait, Colombia, Canada, Chile, Argentina and some others, including Russia (from December 22 and for a week). Eurostar trains running between Brussels and London stopped at midnight.
Meanwhile, scientists are trying to find out whether VUI – 202012/01 is really more adapted to human-to-human transmission and is 71% more diverse (the base reproductive number R, that is, the average number of secondary cases generated by the primary, ranges from 0.39 to 0.93). According to a published report compiled by employees of major British universities and the Center for Viral Research at the University of Glasgow, VUI – 202012/01 differs from other variants of SARS-CoV-2 by 17 mutations at the same time.
"The number of B.1.1.7 infections and the number of regions where B.1.1.7 infections have been reported are growing. B.1.1.7 has an unusually large number of genetic changes, especially in the spike protein. Three of these mutations have potential biological effects that have been described earlier to varying degrees.
1) Mutation N501Y is one of the six key contact residues in the receptor binding domain (RBD), it was identified as increasing the binding affinity with angiotensin converting enzyme 2 in humans and mice.
2) The 69-70del spike deletion is described in the context of evading the human immune response, but it has occurred several times in connection with other RBD changes.
3) The P681H mutation is directly adjacent to the furin cleavage site. <...> As of December 15, there are 1,623 genomes in the B.1.1.7 line. Of these, 519 were identified in Greater London, 555 in Kent, 545 in other regions of the UK, including Scotland and Wales, and four more in other countries," the authors of the report write.
In their opinion, the rapid increase in the number of cases of infection with a new strain indicates the need to strengthen epidemiological surveillance worldwide and conduct studies of antigenicity and infectivity. "The B.1.1.7 line carries a greater number of viral genetic changes than usual. The accumulation of 14 strain-specific amino acid substitutions prior to its discovery was unprecedented for the Covid-19 pandemic. No more than a few mutations were detected in most branches of the SARS-CoV-2 phylogenetic tree. And they accumulate at a relatively constant rate over time. It is estimated that circulating strains of SARS-CoV-2 acquire approximately one to two nucleotide mutations per month," the scientists added. Thus, many of the SARS-CoV-2 genomes sequenced today differ by only 20 points from the earliest ones identified in China at the beginning of the year. Variants with fewer changes are also circulating.
The World Health Organization recommends taking news about the new strain with caution, but without panic, until data on its high pathogenicity and danger have been confirmed: at least four deaths have been recorded so far. Some experts also admit that the accelerated spread of this variant of the virus is an accident, and tourists help him in "moving".
Do not forget that heat and warming can slow down the course of the pandemic, and cold, on the contrary, contribute to it. Earlier, scientists noted that low temperatures put Central Asia, the Caucasus, Eastern and Central Europe, the United Kingdom, the northeastern and midwestern part of the United States, as well as the Canadian province of British Columbia at the greatest risk of spreading infection in winter and early spring.
In addition to the UK, VUI – 202012/01 was found in a sample taken in early December from a Dutch patient. Doctors will find out how he got infected and whether there are related cases. There are nine more infected with the new strain in Denmark and one in Australia. Epidemiologist William Hanage from the Harvard T. Chan School of Public Health noted that, most likely, VUI – 202012/01 has already hit many other countries, and the UK was the first to take the hit, since it has complex genomic monitoring of the causative agent of the current pandemic.
Another important question: will the developed Covid-19 vaccines be effective against the new strain? Moreover, vaccination in the UK, as well as in Russia and the USA, is already underway. According to Sharon Peacock, director of the Covid-19 Genomics UK consortium, VUI – 202012/01 has mutations in the S-protein (covers the shell of the viral particle like thorns or thorns), which some of the vaccines target. Since these drugs produce antibodies against many sites of the spike protein, it is unlikely that one change will make them less effective. Although over time, when new mutations appear, vaccines may have to be adjusted, Peacock added.
As for the Russian vaccine against Covid-19 "Sputnik-V", according to Alexander Ginzburg, director of the Gamalei Scientific Center, it is effective against a new mutation. "The antigenic properties of this virus have not changed, which means that all those vaccines that are made for the pandemic virus remain effective. There is nothing to be afraid of here," Viktor Zuev, head of the microbiology of latent infections at the center, confirmed Ginzburg's words.
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