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These Are The Five Emerging Coronavirus Variants That Worry Health Experts The Most

As soon as the latest strain of coronavirus that caused COVID-19 infection burst onto the world stage in late 2019, medical experts and scientists knew it was bad. However, most in the medical community also thought the virus was stable and would resist mutations – which could buy us time while we develop treatments and vaccines.

Researchers were only partly right. The virus is definitely bad—but it is not so stable after all. Ever since jumping from animals to humans, the virus has been undergoing rapid shifts in mutations leading to several new variants of the original virus in recent months.

The COVID-19 virus is rapidly mutating and presenting challenges for researchers and our vaccine roll out.

Since the pandemic began, new viral versions of the virus have been popping up in communities around the world, and in some cases have outcompeted the existing variants. Although improved surveillance and sequencing efforts might partly explain why these variants are appearing now, some repetition in their patterns suggest the mutations are not random.

“What we’re seeing is similar mutations arising in multiple places,” Adam Lauring, a virologist at the University of Michigan, told Scientific American. “That’s pretty suggestive that these mutations are doing something.”

Most of these mutations in the virus seem to help the virus transmit more rapidly and evade the body’s immune system. In fact, in January, researchers reported for the first time that antibodies from individuals with COVID did not completely neutralize a variant first identified in South Africa. A few people who recovered from the disease also appear to have been reinfected with the mutant virus.

But which variants of the virus have scientists most worried and why?


The 20A.EU1 variant, first identified in Spain, contains a mutation called A222V on the viral spike protein. The spike is a component of SARS-CoV-2 that binds to a receptor on human cells called ACE2, and this attachment helps the virus get inside those cells and infect them.

This spike protein is also what is targeted by human antibodies when they fight back against the infection. Over the course of several months, the 20A.EU1 variant became the dominant one in Europe. Epidemiologists never saw any evidence that it was more transmissible than the original, however. Researchers believe that when Europe began lifting travel restrictions last summer, the variant that was dominant in Spain spread across the continent.


Scientists in the U.K. had been watching the B.1.1.7 variant for some time before announcing in December that it might be at least 50 percent more transmissible than the original form. That announcement was based on data that showed the virus rapidly spreading throughout the nation. And it led to international travel bans and stronger lockdown measures in the U.K.

South Africa

The B.1.351 variant appeared around the same time as B.1.1.7 in the U.K., and it spread quickly in South Africa to become the dominant version in that country. But scientists are most concerned about its E484K mutation which may help the virus evade the immune system and vaccines.

A lab also found that some antibody cocktails, such as one currently being tested by the drug and biotech companies Regeneron and Eli Lilly, may be less effective against mutations present in the B.1.351 variant.


In January researchers reported they had detected two new variants in Brazil, both descendants of a somewhat older common ancestor variant. Although they share mutations with other newly discovered versions, they appear to have arisen independently of those variants.

Vaccines are so far still potent against these strains but we must be vigilant.

So far researchers haven’t seen any major concerns among the vaccines made by by Moderna and Pfizer and their ability to protect against COVID-19 infection. However, Moderna has begun developing a booster shot specific to new variants. Because these two vaccines are more than 90 percent effective, a slight drop in effectiveness would still make them worth using, experts say.

“I’m optimistic this won’t compromise the [COVID vaccines], but obviously, it’s something we’ve got to watch closely,” Lauring told Scientific American. In coming years, he adds, companies may need to retool these vaccines and administer updated versions, much in the same way that flu vaccines are revised each year.

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