Will COVID-19 Vaccines Still Work Against The Variant From India?

The world has a new coronavirus mutant spreading from one continent to another — and it looks like a tough one to stop.

The World Health Organization declared Monday the variant that emerged in India, known as B.1.617, is officially a "variant of concern."

"There is some available information to suggest increased transmissibility of B.1.617," the WHO's Marie Van Kerkhove said Monday from Geneva. Last week, NPR published a story explaining why B.1.617 could be the fastest-spreading mutant on the planet.

At the same time, researchers around the globe have been rushing to figure out if the COVID-19 vaccines available will still be effective against this new mutant. Some preliminary data, published on Sunday and Monday, offers a glimmer of hope.

Like other variants of concern, B.1.617 has more than a dozen mutations. But two mutations in particular have been most concerning, said Ravindra Gupta, a microbiologist at the University of Cambridge. These mutations are found on an important part of the virus — where the immune system attacks.

"So that's why this variant was labeled 'a double mutant,' " Gupta says. "It had these two big mutations, in two big places, and that's what caused all the worries."

Each of these mutations — or similar versions of them — have cropped up separately in other parts of the world, including one in California and one in Brazil. Previous studies have shown that these mutations, individually, give the virus an advantage against the immune system. It reduces the ability of antibodies to fight off the virus.

So what happens when the two mutations come together? The concern, Gupta said, is that the effect of the mutations would add up or even amplify each other. In other words, could the "double mutant" be double trouble for the vaccine?

"So we set up quickly to try and figure out whether this was a real concern," he said.

Gupta and his team took antibodies from people vaccinated with the Pfizer shot and then looked to see how much the two mutations, when combined together, decreased the ability of these antibodies to kill the virus. What they saw was hopeful. The double mutant behaved a lot like the single mutant. It wasn't double trouble.

"There didn't seem to be the addition of one mutant on top of the other," Gupta said. "And that was really quite important because that assumption has caused panic."

The team published its findings online Sunday. At the same time, researchers at Emory University performed similar studies with antibodies taken from 15 people who have been vaccinated with either the Pfizer or Moderna shots. In these studies, the antibodies could still neutralize the B.1.617 variant, but the potency of the antibodies dropped by about sevenfold on average, the authors reported.

"Despite this reduction, all vaccine blood samples ... still maintained the ability to block the Indian variant," said immunologist Mehul Suthar at Emory, who led the study.

Together the data suggests the Pfizer and Moderna vaccines will still work well against B.1.617, just as they do for the variant from South Africa, known as B.1.351. In both cases, the shots will likely offer high protection from death and severe illness, but they may lose some ability to stop mild or asymptomatic infections.

"These findings highlight the need to increase vaccination rates," Suthar said.

That's great news for people in the U.S., where these vaccines are available. But in India, the most common vaccine is the one developed by AstraZeneca and manufactured by the Serum Institute, called Covishield. How will this vaccine fare against B.1.617?

Preliminary evidence suggests this vaccine will also be able to prevent severe cases and deaths, said Rakesh Mishra, adviser to the Centre for Cellular & Molecular Biology in Hyderabad, India.

He and his colleagues have been running experiments similar to the ones Suthar and his colleagues have performed, except with Covishield. The team hasn't published its results yet, but Mishra said they look similar to what other researchers have found with the Pfizer and Moderna vaccines.

"We were actually very relieved," Mishra said, "because this means this variant has not managed to resist the vaccines."

And the world has — once again — gotten lucky, he said; the best tools to fight COVID-19, not only still work, but they are also still powerful. [Copyright 2021 NPR]