Where Has the New COVID-19 Variant Spread in the U.S.?

Digital render of a COVID-19 virus particle with a map of the United States in the background.

Key Takeaways

  • The B.1.1.7 COVID-19 strain is now being reported outside of the United Kingdom, including in the United States.
  • Preliminary research findings show that the B.1.1.7 variant is 56% more contagious than the initial strain. However, there’s no evidence that it causes more severe illness or increased mortality.
  • Another variant related to the B.1.1.7 strain, 501.V2, was discovered in South Africa and might be resistant to vaccines.

The end of 2020 marked the beginning of a new coronavirus variant in the United States. The new variant, called B.1.1.7, arose in Southern England and London in September. In a matter of weeks, the B.1.1.7 strain quickly became the predominant strain of COVID-19 in the United Kingdom.

While scientists expected the virus to mutate, the variant’s high transmission rate makes it challenging to contain, causing a massive burden on hospital resources.

The new virus strain moves fast. Fortunately, scientists are moving fast too. In the span of a few weeks, we’ve learned more about the new strain and its impact on public health. Here’s what we know about reports of B.1.1.7 outside of the U.K., including the first reported cases in the United States.

B.1.1.7 Beyond the U.K.

When the B.1.1.7 coronavirus strain was first announced, several other countries responded by immediately closing their borders to the U.K., but it was not enough to keep the strain from spreading.

The B.1.1.7 strain has spread worldwide, with cases reported in the Netherlands, Japan, Australia, and elsewhere.﻿﻿

In the U.S.

“I’m afraid it’s already in multiple places in the U.S. because of holiday travel and indoor gatherings,” Leo Nissola, MD, an advisor/investigator for COVID Act Now and the National Convalescence Plasma Project, tells Verywell.

On December 30, 2020, the Centers for Disease Control and Prevention (CDC) announced the first B.1.1.7 coronavirus case in the U.S. in Colorado. The person had no travel history, suggesting that the variant was spread from person-to-person contact in the U.S.﻿﻿﻿﻿﻿

B.1.7.7 cases have since been reported in 28 states.﻿﻿﻿﻿﻿﻿﻿

Why Border Closings Will Not Help

In response to the rising COVID-19 cases, Prime Minister Boris Johnson issued a national lockdown for the U.K. However, border closings and travel bans may not have the same effect as they did earlier in the pandemic.

A recent study on travel bans found that countries that enforced travel restrictions, especially international flights, at the start of the pandemic were more effective at containing the spread of the virus. By contrast, countries that delayed their travel bans were more likely to report higher infection rates.﻿﻿

“It’s something we should have done back in the day, back in January or February when we had reports of this deadly illness emerging in China,” Nissola says. “I don’t think there’s any point in locking down the borders right now, especially since the United States has become the epicenter for the virus.”

Quick to Spread, but Not Deadly

The B.1.1.7 strain transmits easily from person to person, and scientists may know why. A new study—which has not yet been peer-reviewed—suggests that the B.1.1.7 strain is 56% more contagious than previous coronavirus strains.﻿﻿

This is lower than the 70% more contagious figure that was first proposed by Prime Minister Boris Johnson. The study also found no evidence that the B.1.1.7 strain is deadlier or caused more severe illness than the initial strain.﻿﻿

There is also evidence of a higher viral load in the B.1.1.7 strain. Preliminary results from another study that has not undergone peer review found that 35% of people with the B.1.1.7 strain had an elevated viral load compared with only 10% of people who did not have the new strain.﻿﻿ Having a high viral load may explain B.1.1.7’s faster rate of transmission.

Another Mutation 

Scientists are also concerned about another coronavirus mutation called 501.V2, which first appeared in South Africa. The 501.V2 shares some mutations with the U.K. variant, such as the 501Y.V2 mutation in the spike protein.﻿﻿ It also has a high transmission rate.﻿﻿ However, it’s still unclear if being more infectious translates to a more severe illness.

The World Health Organization (WHO) says that the 501.V2 variant was found in only a handful of cases.﻿﻿

Still, British Health Secretary Matt Hancock told the BBC that he was more worried about the 501.V2 variant than the B.1.1.7 strain. Nissola says that one reason why scientists are worried is because of 501.V2’s potential to resist vaccines. This may come from the E484K mutation in the 501.V2 strain, which stops antibodies from activating the immune system.﻿﻿

“One concern is that maybe this new variant will make it less susceptible to the immune response created by the vaccine,” Nissola says. “But the jury is still out, so we still don’t know.”

Many Unknowns

There are many unanswered questions about the new strains. The vaccines that have been developed will likely have enough neutralizing antibodies to eliminate the coronavirus, but we don’t know if the virus will continue to evolve and eventually become resistant to vaccines.

“Viruses mutate when it’s under pressure to survive, this can be when giving antibodies or when attaching itself to a new host, such as people who have never been infected before,” says Nissola. “The virus will modify itself to overcome the challenge it’s been put in.”

Nissola cautions that if the U.S. continues to come up short on its response to the pandemic, the virus will have more time to mutate. In which case should expect more coronavirus variants to appear in 2021. If the pandemic response continues to be mishandled, we could see new mutations well into 2022.

Leonardo Nissola, MD


— Leonardo Nissola, MD

Although the new variants do not cause severe infection, that might change. While children are currently less likely to develop a severe infection from the initial COVID-19 virus, scientists are still researching how the new strains could affect children.

Additionally, some early data have suggested that younger people might be more likely to be infected with the B.1.1.7 strain. However, it's still too early to make any firm conclusions.﻿﻿

Reduce Your Risk

The B.1.1.7 strain continues to rise worldwide, and the U.S. has missed the window of opportunity to make a difference by closing the border. Nissola says that the next best option is to mitigate the chances of passing on the virus from person-to-person.

At the government level, Nissola advises stricter quarantine measures after flying and more testing—including genomic testing—at airports to ensure that fewer people go unchecked.

Vaccine efforts also need to be ramped up and better coordinated. The Trump administration initially projected that 300 million COVID-19 vaccines would be ready by January 2021.﻿﻿ As of January 6, 2021, the U.S. has administered 5.92 million doses.﻿﻿

At a public level, Nissola says that it’s important to limit or stop traveling altogether. This means not traveling, avoiding indoor gatherings with people outside of your household, and not eating at indoor restaurants. “It’s the only way we can start to get a grip around this pandemic," Nissola says, adding that you also need to get tested before and after traveling.

What This Means For You

Recent holiday travel has caused a surge in COVID-19 infections. If you have traveled, are planning to travel, or think you might have been in close contact with someone who was sick, immediately self-quarantine and get a COVID test.

The CDC currently recommends quarantining for 14 days, although some places will allow you to end quarantine on day 7 with a negative COVID-19 test.﻿﻿


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