What Does the U.K.'s New COVID-19 Strain Mean for Transmission?

A new coronavirus strain called B.1.1.7 first appeared in September and has quickly caused a wave of infections in the United Kingdom (U.K.). In response to the news, a growing number of countries, including Spain and Russia, have enacted travel bans against the U.K. over the past two weeks.

On January 4, U.K. Prime Minister Boris Johnson ordered a new nationwide lockdown for England in an effort to contain the new variant. The virus strain has already been detected in at least four U.S. states.

While scientists are working around the clock to collect more information about this strain, there are still some unknowns, including how easily it spreads and whether this will affect immunity from a vaccine. Verywell spoke with experts about these concerns and why the mutations causing the B.1.1.7 strain shouldn’t be a cause for panic.

Viruses Mutate All the Time

A mutation isn’t necessarily a bad thing. Viruses are expected to mutate, Brian Labus, PhD, MPH, an epidemiologist, infectious disease expert, and public health professor at the University of Nevada, Las Vegas, tells Verywell.

In fact, Steve Russell, MD, PhD, and the CEO and co-founder of Imanis Life Sciences, tells Verywell that SARS-CoV-2—the coronavirus that causes COVID-19—has been acquiring a rate of 1 to 2 mutations a month ever since it first appeared in Wuhan, China. Because of mutations, Labus says that the coronavirus strain from China isn’t the same coronavirus circulating in the United States and other parts of the world.

“Everything that has genetic material will undergo mutation, and that’s really the driving force behind evolution. But viruses mutate much more frequently, especially RNA viruses, like coronaviruses,” Angela Rasmussen, PhD, a virologist at the Center for Global Health Science and Security at Georgetown University, tells Verywell.

Viruses can’t replicate by themselves and require a host cell. Once infected, the virus can hijack the gene-editing machinery in cells to make copies of itself. However, Rasmussen explains that viruses are typically error-prone and can end up making random mutations during replication. Even the latest coronavirus, which came prepared with a proofreading mechanism, is bound to make a mistake eventually.

Rasmussen says mutations are most likely to stick around if they provide a competitive advantage for the virus. “While a mutation is normal, it isn’t guaranteed that it will make the virus better,” she says.

With the B.1.1.7 variant, the rapid accumulation of mutations is particularly notable. “We expect viruses to mutate over time,” Labus says. “Normally, coronaviruses will gradually accumulate mutations as they’re spreading in a population. But for this one, a bunch of mutations popped up all at once.”

Are the Mutations in the B.1.1.7 Strain More Contagious?

The B.1.1.7 variant has 23 different mutations. Some of these mutations exist in other variants and some are brand new. The concern is that the B.1.1.7 strain outcompeted other coronavirus strains, so when it emerged in the fall in Southern England, it quickly circulated to most of the U.K.

However, it’s too early for experts to know why the B.1.1.7 strain has become dominant or if it spreads faster than other strains, Russell says.

At a news conference, Prime Minister Boris Johnson announced the new coronavirus may be up to 70% more likely to infect people. Rasmussen says 70% isn’t a reliable number because the percentage is based on a model—not an actual experiment.

“[Researchers] modeled the data and said it looks like it's 70% more transmissible, but they haven’t done any experiments to prove that it’s true," Rasmussen says. "The real answer right now is that we don’t actually know it’s more transmissible. If it is, then there might be something going on in one or more of these mutations in this variant to make it that way.”

Another explanation could be that people might be shedding the virus, which Rasmussen says the viral load data seems to suggest. Alternatively, Rasmussen says that 8 of the 23 genetic mutations are in the spike protein—the section involved in binding to cells and infecting them with the virus—and may affect transmission.

“It’s very much an active area of research, but we can’t say for sure that the rapid increase and prevalence is suggestive that it might have some advances that let it transmit more readily,” she says.

No Evidence of Severe COVID-19 Infection

Russell says enough people have become infected by the B.1.1.7 variant to look at the severity of infection. “By December the 13, the U.K. passed a thousand cases [from the strain],” he says.

Currently, there is no evidence suggesting that this new variant leads to more severe infections. According to the Centers for Disease Control and Prevention (CDC), there is also no increased risk of death. However, more observational and animal studies are needed to confirm these results.

Vaccine Protection Despite New Mutations

While it still needs to be evaluated, Russell says he’s confident the vaccines will give immunity to this strain despite a few mutations in the spike protein.

“Essentially, it’s the same protein. It just looks different," he says. "Think of a friend you recognize, and one day they’re wearing a hat. You should still be able to recognize that it’s your friend.”

Because it’s still early in the life of this strain, Rasmussen says there is a concern of a mutation in the spike protein called N501Y potentially neutralizing antibodies. A recent preprint study showed that the N501Y mutation in the B.1.1.7 strain increased the virus's ability to infect cells.

However, new data from the University of Texas’s Menachery lab looked at the N501Y mutation in plasma from people who survived COVID-19 infection. While the data has not been published or peer-reviewed in a journal, the results suggest that antibodies were still capable of stopping the virus.

“This data is preliminary but encouraging," Rasmussen says. "It suggests that antibodies to any coronavirus variant will still neutralize at least the N501Y mutation. But ultimately, we have to do more studies to look at the seven other different mutations in the spike protein. The good news is that antibodies look like they’ll still be protective against one part of the spike protein.”

Vaccines may also be beneficial against this coronavirus variant due to their ability to boost the immune system.

“When somebody is vaccinated or infected with the virus, there is more than one type of antibody being produced in response to the virus,” Rasmussen says. “A virus has to mutate quite a bit to escape the polyclonal response, which means a lot of different antibodies that bind to other targets. So, I think the chances are good that the vaccines we have will be protective against this particular variant."

Will This Virus Spread To Other Countries? 

A potential reason the United Kingdom may have detected this strain at all is because of its investment in genomic surveillance. Rasmussen says that the U.K. is actively searching for new coronavirus mutations. They sequence 10% of their total number of COVID-19 cases to determine the viral genome sequencing.

“In the U.S., we don’t do near that amount of genomic surveillance, and so as a result, we’re less likely to detect a variant like this that has emerged,” she says.

Considering the out-of-control transmission in the United States and other countries, Rasmussen says it’s likely this virus strain is already present. At least four U.S. states and 33 countries have identified the new variant, including Colorado, Florida, New York, and California.

On December 22, the CDC announced a possibility that the United States may have the B.1.1.7 strain and that it may be undetected. The United States has sequenced only 51,000 out of the 17 million coronavirus cases.

The United States is currently leading the world with the highest number of COVID-19 cases and deaths. According to the CDC COVID-19 tracker, there are presently 20,732,404 cases and 352,464 deaths.

Rasmussen adds there are confirmed reports of B.1.1.7 strain in other European countries such as Denmark, the Netherlands, Italy, and Australia.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.