What to Know About B.1.1.7, the Coronavirus Variant That Could Soon Dominate the U.S.

A highly infectious coronavirus variant that was first detected in the U.K. is now rapidly spreading in the U.S. The variant, B.1.1.7, has been detected in at least 34 states so far and is expected to continue circulating.

A new preprint study estimates that cases of the variant are doubling in the U.S. every nine days, with an increased transmission rate of up to 45 percent. “Our study shows that the U.S. is on a similar trajectory as other countries where B.1.1.7 rapidly became the dominant SARS-CoV-2 variant, requiring immediate and decisive action,” the researchers wrote.

In a January report, researchers from the Centers for Disease Control and Prevention (CDC), warned that B.1.1.7 could become the dominant strain of SARS-CoV-2, the novel coronavirus that causes COVID-19, by March. Another report released by the U.K. government’s science advisory group found that there is a “realistic possibility” that a B.1.1.7 infection “is associated with an increased risk of death” when compared to other strains of the virus.

The findings are “concerning,” Anthony Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases, said in a January 35 interview on Today. “The data has not come out officially, but taking a look at the preliminary data that the U.K. scientists have analyzed, I’m pretty convinced that there is a degree of increase in seriousness of the actual infection, which we really have to keep an eye on.”

Here’s what experts know about the B.1.1.7 coronavirus variant so far, and what you can do to protect yourself.

What is B.1.1.7 and where did it come from?

Coronavirus variants, like B.1.1.7, began to emerge after the original, dominant strain of SARS-CoV-2 began to mutate. It’s important to remember that all viruses mutate. They’re not always a cause for concern, but others are worth watching when they begin to spread rapidly.

“When SARS-CoV-2 replicates, errors get made—not infrequently,” Stanley H. Weiss, M.D., professor at both the Rutgers New Jersey Medical School and the Dept. of Biostatistics & Epidemiology at the Rutgers School of Public Health previously told Prevention.com. “Most of these are defective, don’t replicate very well, don’t carry on, and don’t matter. Occasionally, the wrong set of combinations and mutations can occur.”

B.1.1.7 is notable for its number of mutations—six key mutations, to be exact— including some that directly involve the spike protein, which has generated “great interest,” says Dr. Weiss, as this is the piece of the coronavirus that latches onto human cells.

The CDC reports that B.1.1.7 is estimated to have emerged in the U.K. in September 2020 and that it is associated with “more efficient and rapid transmission.” It’s now been detected in several countries, including the U.S. and Canada.

How many states have confirmed B.1.1.7 infections?

The B.1.1.7 variant was first identified in the U.S. in December. A Colorado man in his 20s with no reported travel history tested positive and recovered in isolation.

Since then, at the time of publication, nearly 1,000 B.1.1.7 infections have been identified in 34 states, according to CDC data. Florida and California, in particular, have significantly higher B.1.1.7 case counts. That number is expected to rise nationwide in the coming months.

Does the B.1.1.7 variant cause different COVID-19 symptoms?

There’s a lot scientists don’t know about this variant, but “symptoms do not appear to be different at this point,” says Prathit Kulkarni, M.D., assistant professor of medicine in infectious diseases at Baylor College of Medicine in Houston.

As a result, there’s “no way” for you to know whether your symptoms might be due to the original strain of SARS-CoV-2 or B.1.1.7, says Thomas Russo, M.D., professor and chief of infectious disease at the University at Buffalo in New York. “Only testing will tell if you have this variant,” he says.

That means you should still be mindful of the most common signs of COVID-19: fever, chills, shortness of breath, fatigue, muscle or body aches, headache, new loss of taste or smell, sore throat, congestion or runny nose, nausea or vomiting, or diarrhea.

Is B.1.1.7 really that much more contagious?

According to the data we have so far, yes. In fact, one preprint study from the London School of Hygiene and Tropical Medicine estimates that the B.1.1.7 variant is 56 percent more contagious than the original strain of SARS-CoV-2. Another study, from researchers at the Imperial College London, found that B.1.1.7’s viral reproduction—the average number of people an infected person passes the virus on to—was 1.45. The number before the variant emerged was 0.92.

B.1.1.7 was first detected in the U.K. in September, but the variant made up a quarter of cases in London by November, per the BBC. By the week of December 9, it was responsible for 60 percent of the confirmed COVID-19 cases in London. “There is emerging data that suggests the new variant is about 50 to 60 percent more contagious than the previously most widely circulating strain,” Dr. Kulkarni says.

There is also data to suggest that B.1.1.7 may be more likely to infect children, scientists from the U.K.’s New and Emerging Respiratory Virus Threats Advisory Group told reporters in mid-December. “We haven’t established any sort of causality on that, but we can see it in the data,” said Neil Ferguson, a professor and infectious disease epidemiologist at Imperial College London, per Reuters. We will need to gather more data to see how it behaves going forward.”

Are the available COVID-19 vaccines effect against B.1.1.7?

Currently, the makers of the COVID-19 vaccines authorized for use in the U.S.—Moderna and Pfizer—have stated that their vaccines are up to 95 percent effective against B.1.1.7. Novavax, which is currently in phase 3 clinical trials in the U.S., announced in late January that its vaccine was nearly 86 percent effective against B.1.1.7.

What should you do to protect yourself from B.1.1.7?

In addition to B.1.1.7, other highly infectious variants—including those that emerged from Brazil and South Africa—have been detected in the U.S. This shouldn’t make you panic, but it should serve as a reminder that now is not the time to let up on “following common-sense precautions,” says infectious disease expert Amesh A. Adalja, M.D., senior scholar at the Johns Hopkins Center for Health Security.

“The core public health recommendations also remain the same,” says Dr. Kulkarni. Keep avoiding large gatherings, social distancing from those outside of your household, washing your hands frequently, and wearing a face mask that fits snugly over the nose and mouth.

For added protection, particularly in high-risk settings like on a crowded bus or in line at a busy grocery store, experts (including Dr. Fauci) say you may choose to double mask (wear a surgical or KN95 mask with a cloth mask on top, as long as it doesn’t restrict breathing) or wear a face shield over your face mask.

Dr. Russo emphasizes “it’s likely we’ll have additional COVID-19 variations in the future” and we’ll have to adjust our response accordingly—so when you have the chance to get the vaccine, it’s crucial that you do so to protect yourself and those around you.

This article is accurate as of press time. However, as the COVID-19 pandemic rapidly evolves and the scientific community’s understanding of the novel coronavirus develops, some of the information may have changed since it was last updated. While we aim to keep all of our stories up to date, please visit online resources provided by the CDC, WHO, and your local public health department to stay informed on the latest news. Always talk to your doctor for professional medical advice.