The coronavirus mutation in the UK is worrying, but not terrifying


A new, mutated form of the novel coronavirus that appears to be more transmissible than the original has raised alarm bells in the UK and around the world. It does not appear to cause more serious illness, and the newly available vaccines appear to protect people from it. However, on December 19, after the announcement that the variant, dubbed B.1.1.7, had suddenly accumulated 17 mutations and was spreading rapidly in the UK – the country’s Prime Minister Boris Johnson announced tighter lockdowns there. And many European countries have cut off travel from this nation.
The response from the United States has been mixed, with politicians such as New York State Governor Andrew Cuomo calling first to suspend airline flights from the UK and then to request mandatory tests of travelers. But scientists like Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, say the flight bans are likely too late to stop the variant from spreading to the United States. “I wouldn’t be surprised at all if it’s already there, ” he said Hello america December 22

Based on mathematical models, calculations by the COVID-19 Genomics UK consortium suggest that B.1.1.7 could be up to 70% more transmissible than the original virus. “It’s a shocking assessment, clearly something new that is circulating,” said Ali Mokdad, a population health expert at the University of Washington. “Any changes there are of concern to us. It is a stubborn and opportunistic virus. ”

Some researchers, however, doubt that the rapid spread of the new variant in the UK necessarily means that it is more transmissible. “I agree that we should look at these things. But until we have data, we really have to be careful what we say, ”says Vincent Racaniello, a virologist at Columbia University. The best information on transmissibility will come from animal studies investigating whether this variant moves more easily from creature to creature, and that work has yet to be published. Because the majority of COVID-19 outbreaks are caused by super-spreaders, racaniello says, it’s conceivable that one person or a few individuals will widely spread the new variant.

But others do not agree. In the UK, the variant has increased steadily over time, not suddenly as one would expect from a mass-market event, says Scott Weaver, immunologist in the medical branch of the University of Texas (UTMB).

In addition, eight of the 17 variants B.1.1.7 new mutations are on the spike protein: the part of the coronavirus shell that allows it to bind to receptors on the surface of cells and infect cells. One of the mutations in the spike protein, called N501Y, appears in another new variant from South Africa and appears to improve the binding capacity of the virus. A better link could, in theory, lead to more transmission.

Michael Farzan, an immunologist at the Scripps Research Institute, says that the fact that the N501Y mutation appears to have appeared independently multiple times in different geographic areas is further evidence that it gives the virus some sort of advantage. Other advanced protein mutations, including one called D614G which has been observed in the United States, allow the virus to replicate better in the upper respiratory tract of mice, rather than the lower airways. This arrangement could make it easier for the virus to spread through sneezing and coughing. The D614G variant has been around for some time, however, and it has not been shown to be more contagious in humans or to create more severe symptoms.

Mutations may not help this version of the SARS-CoV-2 virus escape all the cells and proteins that our immune system uses to neutralize it. The first data from the laboratory of Vineet Menachery, microbiologist at the UTMB, suggest that the N501Y variant is just as sensitive to our defenses as the original virus. But these genetic alterations could be bad news for treatments with monoclonal antibodies against the virus. A December 1 pre-print study found that the mutations caused changes in a segment of virus very close to regions recognized by monoclonal drugs made by pharmaceutical companies Eli Lilly and Regeneron, making it more difficult for antibodies to bind and neutralize. .

According to Farzan and others, the most pressing question may be how the new variant will affect existing COVID-19 vaccines and the development of new ones. It does not appear that B.1.1.7 can withstand the authorized vaccines developed by Pfizer and Moderna, respectively, or those made by other companies that are still being tested. Yet the fact that mutations build up in the spike protein could mean that vaccines may, after an extended period of time, become somewhat less effective. This problem would force vaccine developers to adapt their products to ensure they can target new versions of the virus. “A lot of people think it’s going to be like the flu, with a new vaccine every year,” Weaver says.

He and others say mutations in the virus are not a reason for people to skip any of the vaccines because they are still very effective. They protect over 90% of people from COVID disease. And there has been no sign in clinical trials that the virus – including any newer variants – is resisting vaccination efforts.

The new British mutant makes it even more important for people to use public health measures such as physical distance and wearing a mask, says Racaniello. These strategies will slow the spread. “While vaccines should always work, we are at even greater risk of overwhelming our hospitals and healthcare workers,” says epidemiologist Lisa Gralinski of the University of North Carolina at Chapel Hill. “We are already short of health care in the United States. The last thing we need is more cases to come faster. ”

Like Fauci, Gralinski says the variant is probably already in the United States. . The United States, on the other hand, does not have such a centralized effort. “We’re flying a bit blind right now,” Gralinski says. “We have to assume that the variant is here.”

Mokdad’s group and others are now working over the December break to sequence existing U.S. samples of the virus. A more transmissible variant could explain, for example, the recent spike in cases in California. Health officials could have missed the new version, he says, and speculated that the rapid increase in COVID-19 cases was due to the increase in travel around Thanksgiving. “It’s a wake-up call for all of us to know as soon as possible to make sure we know what’s going around – especially how it will impact the vaccine,” Mokdad says. “It’s a race against time.”

Learn more about the Scientific American coronavirus outbreak here. And read the coverage of our international magazine network here.


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