What We Know About The New U.K. Variant Of Coronavirus


December 22, 20203:56 PM ET

A new variant of the coronavirus is spreading rapidly in England and raising international alarms. This new variant now accounts for more than 60% of the cases in London. And scientists say the variant is likely more contagious than previous versions of the virus.

Health officials have closed international travel to the United Kingdom. The British government has locked down much of the country. And scientists all over the world are rushing to figure out how the virus mutated and how big a threat the new variant poses.

Here’s what we know so far:

  • The variant has a large number of mutations.

Throughout this pandemic, SARS-CoV-2 — the virus that causes COVID-19 — has been mutating. It has accumulated about one or two mutations each month. That’s not surprising. Viruses always mutate.

But this new variant in the U.K., called B.1.1.7, has acquired mutations much quicker than scientists expect. The variant has 17 different mutations in its genetic code. And eight of those mutations occur in a critical part of the virus, called the spike protein, which reaches out and binds to human cells during the initial stages of infection.

  • The new variant likely is more transmissible than previous versions of the virus.

When scientists first detected B.1.1.7 in late September, it rapidly took over parts of England, pushing out other forms of virus. By early December, the new variant had pushed out other forms of the virus in London and become the dominant one.

This rapid rise suggests B.1.1.7 is more transmissible than other forms of the virus. “There’s no hard evidence, but it seems most likely,” says biochemist Jeremy Luban at the University of Massachusetts Medical School. “So if a person sneezes on a bus, the new variant is more likely to infect other people than the previous form of the virus.”

To figure out transmissibility for certain, scientists have to bring B.1.1.7 into the lab and see if it’s better at infecting cells and spreading between animals.

  • Even if the variant is more transmissible, it might not change the course of the pandemic.

SARS-CoV-2 is already spreading quickly around the world. So a small increase might not make a big difference. It depends on how much better B.1.1.7 spreads.

In the end, how quickly the virus spreads depends on many factors, including people’s behavior in a community. That is, whether they wear masks, physically distance and avoid big gatherings. Those factors could be more important than whether B.1.1.7 arrives in a community, says virus expert Pei-Yong Shi at the University of Texas Medical Branch. “With all these human interventions, it’s hard to predict the course of the pandemic.”

  • The variant has likely spread to many countries around the world, including the United States.

Researchers have already detected it in Denmark, the Netherlands and Australia.

The U.K. has been vigilant about looking for new variants and following them. Other countries, including the U.S., haven’t been tracking variants as closely. So new variants, such as B.1.1.7, have likely gone undetected.