The mutation – called E484K – has been found in a variant of the coronavirus that was first seen in South Africa two months ago. This variant has now spread to 12 other countries.
Penny Moore, an associate professor at the National Institute for Communicable Diseases in South Africa, called the mutation “alarming.”
“We fear that this mutation may have an impact, and what we do not know is the extent of the impact,” she said.
E484K is called an “escape mutant” because it has been shown that it may be able to escape some of the antibodies produced by the vaccine.
“I’m worried,” said Alex Sigal, a virologist at the Africa Health Research Institute.
Sigal, Moore, and other researchers studying the E484K mutation still need to complete their work in the laboratory to see if the vaccine is less effective against this new variant.
Based on what they have seen so far, they say they highly doubt that E484K will render coronavirus vaccines useless. Rather, they believe that there is a possibility that the mutation – alone or in combination with other mutations – may reduce the vaccine’s effect against the variant.
They also worry that E484K may be an indication that the new coronavirus is showing its ability to change before our eyes. If this mutation happened within a few months, other problematic mutations could follow.
“This virus may be taking the first steps down a fairly long path toward vaccine resistance,” said Andrew Ward, a structural virologist at Scripps Research in La Jolla, California.
“It’s the beginning of a long haul,” Moore said. “That’s what really shook me about this. It’s a sober wake-up call.”
“Escape mutant” is like a disobedient child
To understand the potential danger posed by the E484K mutation, imagine a teacher in front of a classroom full of noisy first graders.
After several months of trying to get his class under control, the teacher finally nails it. She makes them sit still in their chairs.
But after a while, one child leaves the class and another takes a seat. This new kid – this new little villain – is not sitting down. The teacher’s technique for reassuring the children does not work with him.
The teacher here is the vaccine and the furious student is the E484K mutation.
When the vaccines used in the United States were tested this summer and fall, they nailed it and almost conquered the virus for submission. But since then, parts of the virus have sometimes swapped for new bits, and sometimes the new bits do not behave.
What they found is that E484K challenges the ability of some antibodies to neutralize the virus.
While attention has been focused on the E484K, researchers are also keeping an eye on other mutations in the variant.
The next step is to test these mutations against antibodies created by vaccines – this is the work that researchers are doing now and hope to be able to announce within the next few weeks.
“Escape mutant” is also available in variant in Brazil
However, although E484K – alone or in combination with other mutations in the variant – ends up being a problem, the variant is unlikely to escape all antibodies produced by vaccines, given that the vaccines produce many antibodies.
The concern is more about what happens when the virus mutates again and again.
It’s not that coronavirus is such a fast mutator – in fact, Sigal, one of the South African researchers, called it “a real slowpoke.” It is that the virus is spreading so fast around the world and every time it goes from person to person, it gets a new chance to mutate.
“It creates more opportunities for the virus to learn to be resistant to the vaccine,” said Paul Bieniasz, a virologist at Rockefeller University. “In time, it is likely to stay away from vaccine efficacy, but we will not fall off a cliff tomorrow.”
Such bad behavior was not expected from a coronavirus, which has always been considered relatively stable, Sigal said.
“This virus really showed us that it can adapt and be able to escape,” he said. “It just goes back to the first rule of virology: do not underestimate your virus.”