Lessons from the UK on a more contagious Covid-19 variant


LONDON – The UK has become a testing ground for how a more contagious and possibly deadlier variant of coronavirus spreads through communities, displacing its less communicable ancestors and complicating vaccine launches and uprising. of the locks.

The variant has already been identified in more than 70 countries and 40 US states, and its advancement in Britain could help scientists understand its likely trajectory in the US These charts show the spread of the variant in the UK and what British scientists are learning about it – including its increased transmissibility and lethality.

“Increasingly, since this version of the virus was discovered, we have been experiencing two separate pandemics,” said Jason Leitch, Scotland’s national clinical director. “That is a warning for other countries.”

Seven-day advance rate of new Covid-19 cases in the UKLondonLondonBirminghamBirminghamSheffieldSheffieldBelfastBelfastEdinburghEdinburghCardiffCardiff

Seven-day rolling rate of new cases

Per 100,000 inhabitants

100175250325

Proportion of UK variants of new cases in England

September 3October 1stNovember 5thDecember 31stFebruary 4th0fifty100%

Source: Public Health England (map); Second generation surveillance system (graphic)

British scientists spotted the new variant in November and, in early December, traced its first appearance in the UK to the county of Kent in southern England in September. The country was closed in November to suppress a deadly wave of infection that had been building up since the fall. British public health officials were baffled by the spread of the virus in southern England despite those restrictions.

When the scientists examined the variant’s genome, they found an unusually large number of mutations, some of which pointed to the possibility that the new variant could spread more rapidly than pre-existing versions. Additional sequencing, and a test quirk that served as a reliable proxy for the presence of the variant, revealed how quickly the variant reached dominance.

The total number of

contacts that

became cases

Percentage of all contacts that became cases, by region

The total number of

contacts that

became cases

Percentage of all contacts that became cases, by region

The total number of

contacts that

became cases

Percentage of all contacts that became cases, by region

Percentage of all contacts that were converted

cases, by region

The total number of

contacts that

became cases

When the blockade was lifted in early December, the new variant became national. The overall rate of cases per 100,000 people quintupled in London, and the new variant was soon detected in almost every corner of the UK. On January 4, another stricter national blockade was imposed to stop its spread. Since then, the case load has receded and the government has published plans for a staggered reopening in the coming months.

Public health officials began investigating the contact patterns of people known to be infected with the new variant, now widely known as B.1.1.7. They found evidence that people infected with the variant infected more people than those infected with the previously dominant strain. That finding bolstered the genetic analysis that points to a more transmissible version of the pathogen.

“We haven’t seen anything like the UK variant in terms of its growth rate, in terms of its transmissibility,” said Nick Loman, professor of microbial genomics and bioinformatics at the University of Birmingham.

More worryingly, when public health officials and teams at UK universities began examining clinical data known to be infected with B.1.1.7, they detected signs that the variant could be associated with an increased risk of death.

Findings from various studies on the increased or decreased probability of dying from Covid-19 if

infected with UK variant versus previous variant

Findings from various studies on the increased or decreased probability of dying from

Covid-19 if you are infected with the UK variant versus the previous variant

Findings from various studies on increasing or decreasing the likelihood of

die from Covid-19 if you are infected with the UK variant versus the previous variant

Findings from various studies on the

more or less likely to die

from Covid-19 if you are infected with the UK

variant vs. previous variant

A preliminary analysis, from Scotland, suggested that infection with the variant could be 65% more likely to result in hospitalization and 37% more likely to end in death than contracting the older version of the virus. Scientists say these findings are not definitive, and some studies suggested that the link to higher mortality was weak or that the variant may even be associated with a lower risk of death.

Still, the evidence was enough for a panel of scientists who advised the UK government to say this month that B.1.1.7 is likely to carry a higher risk of hospitalization and death than established versions.

Patient surveys conducted by the UK Office for National Statistics between November and January yielded another finding: infection with B.1.1.7 can lead to slightly different symptoms, which can help doctors spot potential cases.

Percentage of Covid-19 patients in England who report each symptom, according to the variant in question

infected with

Percentage of Covid-19 patients in England who reported each symptom, based on which

variant with which they are infected

Percentage of Covid-19 patients in England reporting each symptom, according to

which variant are they infected with

Percentage of Covid-19 patients in England

reporting each symptom, based on which

variant with which they are infected

The classic symptoms of Covid-19 – fever, cough, and shortness of breath) were slightly more common among those with the new variant than among the old ones. Patients who reported loss of taste or smell were less frequent. And gastrointestinal complaints were more frequent in the case of the new variant.

One consolation for the UK, according to public health officials, is that the new variant is now so dominant and so communicable that other variants of interest to epidemiologists, such as those identified in South Africa and Brazil, have not gained much traction. . Another reason for optimism is that laboratory tests and some clinical studies, as well as real-world vaccination in the UK, suggest that the variant can be neutralized by the current range of vaccines.

As highly communicable coronavirus variants spread across the world, scientists are racing to understand why these new versions of the virus are spreading faster and what this could mean for vaccination efforts. New research says the key may be spike protein, which gives the coronavirus its unmistakable shape. Illustration: Nick Collingwood / WSJ

Dr. Philip Dormitzer, Pfizer Inc.’s

The chief scientific officer for viral vaccines told UK lawmakers on Wednesday that the company was seeing protection against the UK variant in real-world data from Israel and the UK “equivalent to the protection we saw in controlled trials before. that variant circulated “.

Still, the variant’s rapid advancement and unusual features mean it remains a concern, disease experts say, especially if vaccine launches don’t keep pace.

Cumulative number of US Covid-19 samples that tested positive for the UK variant

Cumulative number of US Covid-19 samples that tested positive for the UK variant

Cumulative number of US Covid-19 samples that tested positive for the UK variant

Cumulative Number of US Covid-19 Samples

testing positive for UK variant

“It’s a new beast,” said Eric Topol, professor of molecular medicine at Scripps Research in California. He said he did not think it was widely appreciated that the new variant could create a new pandemic, “driven by a virus that is harder to fight.”

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Write to Jason Douglas at [email protected] and Joanna Sugden at [email protected]

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