What Experts Know About the Current Coronavirus Variants

The appearance of highly transmissible versions of the pandemic coronavirus has the world’s medical community on high alert

An illustrative image of medical syringes in front of the logos of various companies working on the Covid-19 vaccine, displayed on a screen.
Currently accessible Covid-19 vaccines seem to protect people against the emerging variants so far. Photo illustration by Artur Widak/NurPhoto via Getty Images

Several coronavirus variants have emerged in recent weeks that spread from person to person more easily than the dominant strain that's driven the Covid-19 pandemic thus far. The variants were first identified in the United Kingdom, South Africa and Brazil, Andrew Joseph reports for STAT. New research suggests yet another variant has emerged in California as well.

The presence of coronavirus variants raises several questions about how the pandemic will play out in the coming months. Even countries that have taken strict precautions to prevent the virus’ spread, like Denmark, have seen a rise in variant infections, Michael Birnbaum and Martin Selsoe Sorensen report for the Washington Post. Early data suggests that the U.K. variant may not only be easier to spread, but also more deadly, Elizabeth Cohen reports for CNN.

Currently accessible Covid-19 vaccines still appear to protect people against the emerging variants, and officials emphasize the importance of following through on vaccine distribution plans, reports National Geographic’s Michael Greshko.

“There is a very slight, modest diminution in the efficacy of a vaccine against it, but there’s enough cushion with the vaccines that we have that we still consider them to be effective,” Anthony Fauci, the nation's leading infectious diseases official, said Monday on the “Today” show.

What is a variant and where does it come from?

A variant is a version of the coronavirus with “an evolutionary edge,” STAT reports.

The virus, called SARS-CoV-2, has a genetic code written with RNA instead of DNA. Sometimes, as the virus is making copies of itself, it makes a mistake when re-writing its RNA. Coronaviruses are usually able to catch and correct their mistakes, but sometimes a genetic typo makes its way into a new generation of viruses.

Sometimes those typos have no effect on the virus, and sometimes they actually hurt the virus. But the recently-identified variants, through some combination of several typos, got an advantage: increased transmission.

Viruses with advantages tend to become more common over time. Early in the pandemic, a mutation called D614G boosted the coronavirus’ infectiousness. As Covid-19 spread around the world, viruses with the D614G mutation were most prevalent, per STAT. Concerns over the possibility that variants could develop in minks led European countries to cull millions of the animals, which are raised in farms for their fur.

Scientists identified highly transmissible variants of the coronavirus in the U.K. and South Africa in December, and Brazil and California in mid-January, per National Geographic.

In terms of the virus’ ability to infect humans, “compared to SARS or MERS, it [SARS-CoV-2] was already quite capable, but that doesn’t mean that it couldn’t become more capable,” says Scripps Research Institute infectious disease expert Kristian Andersen to STAT. “And that’s what we’re observing now.”

Not all of variants have begun circulating in the United States. In an effort to prevent new variants from entering the U.S., President Joe Biden reinstated a ban on non-U.S. residents from entering the country from the European Union, U.K., Ireland and Brazil. Biden also added South Africa to the list of restricted countries, David Shepardson reports for Reuters. New CDC rules that went into effect yesterday require international air travelers to provide proof of a negative Covid-19 test in order to enter the country.

Are the variants more dangerous?

In the U.S., the CDC warned that the U.K. variant of the coronavirus may become the most common form of the virus by March, Erin Garcia de Jesus reports for Science News. It has already been identified in 22 states, per CNN, and it is particularly common in Florida and California.

The variant is about 30 to 70 percent more contagious than versions of the virus that have circulated for the past year, per the Washington Post, and early data suggests it may be more deadly as well.

Among men in their sixties, “the average risk is that for 1,000 people who got infected, roughly 10 would be expected to unfortunately die with the virus. With the new variant, for 1,000 people infected, roughly 13 or 14 people might be expected to die," the U.K.’s chief science adviser Patrick Vallance said on Friday. “…You will see that across the different age groups as well, a similar sort of relative increase in the risk."

The CDC is now reviewing the U.K.’s data, reports CNN.

Elsewhere, the variants identified in Brazil and South Africa may be able to infect people who have already recovered from one bout of Covid-19, per STAT. That means that a city like Manaus, Brazil, where about three-quarters of residents had been infected with the coronavirus already, is still at risk of a rise in new infections because the immunity to the first infection is no longer protective against the new variant.

How can I protect myself?

Experts strongly advise rigorously following public health guidelines. Those guidelines vary by region but generally include keeping six feet of distance between yourself and others, wearing masks, washing hands and limiting time spent indoors with those from outside your household.

“These measures will be more effective if they are instituted sooner rather than later,” the researchers say, per Science News.

Getting vaccinated when possible would also provide protection against the coronavirus—even a variant. The vaccines produced by Moderna and Pfizer work by creating tiny particles from the surface of the coronavirus, called spike proteins. The proteins don’t cause an infection, but they do teach the immune system how to fight against anything covered with similar spike proteins.

“The variants do have changes in the [virus’s] spike protein, but not enough to make the vaccine not protective,” said Arnold Monto, the acting chair of the U.S. Food and Drug Administration’s Vaccine and Related Biological Products Advisory Committee, in a video interview with Howard Bauchner of the medical journal JAMA. “It looks like [existing vaccines] should work, and we’ll know more definitively in the next couple of weeks.”

Moderna announced on January 25 that their vaccine is equally effective against the original coronavirus strain and the U.K. variant, but that it is less effective—but still protective—against a variant from South Africa, Denise Grady reports for the New York Times. The company will soon develop a booster shot to increase protection against the South Africa variant.

“We’re doing it today to be ahead of the curve should we need to,” says Moderna’s chief medical officer Tal Zaks to the Times. “I think of it as an insurance policy. I don’t know if we need it, and I hope we don’t.”

Get the latest stories in your inbox every weekday.