New coronavirus variants may cut vaccine effectiveness


The good news is that the new mutations of the COVID-19 coronavirus found in Britain, South Africa, Brazil, and other countries don't appear so far to be inherently more deadly than other variants. The bad news is that because they spread more easily, more people are getting infected and dying — and the rise in infections is giving the virus more chances to mutate. Worse, the new mutations appear to modestly curb the effectiveness of the vaccines from Moderna and Pfizer/BioNTech, researchers reported Wednesday.
Researchers at New York's Rockefeller University and National Institutes of Health took blood from 10 people inoculated with either the Moderna or Pfizer vaccine and tested those samples with coronavirus variants from Britain, South Africa, and Brazil. With some of the samples, the antibodies spurred by the vaccine were up to three times less effective at blocking the virus from infecting cells, Rockefeller's Dr. Michel Nussenzweig said. "It's a small difference but it is definitely a difference."
Neither these findings nor separate, more hopeful research from Pfizer have been peer-reviewed. Pfizer said Wednesday that a second study has shown its vaccine to be just as effective against several mutations found in the U.K. Moderna and AstraZeneca are also testing their vaccines against various mutations.
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The vaccines still protect people against developing COVID-19, immunologists say. "We don't want people thinking that the current vaccine is already outdated. That's absolutely not true," said E. John Wherry at the University of Pennsylvania. "There's still immunity here ... a good level of protection," but the mutations "do in fact reduce how well our immune response is recognizing the virus." The vaccines may have to be tweaked — a fairly easy process for Pfizer and Moderna's vaccines — and countries shouldn't count on vaccinations alone, experts caution.
"We've got an arms race between the vaccines and the virus," Dr. Buddy Creech, a vaccine specialist at Vanderbilt University, tells The Associated Press. "The slower we roll out vaccine around the world, the more opportunities we give this virus to escape" and mutate.
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Peter has worked as a news and culture writer and editor at The Week since the site's launch in 2008. He covers politics, world affairs, religion and cultural currents. His journalism career began as a copy editor at a financial newswire and has included editorial positions at The New York Times Magazine, Facts on File, and Oregon State University.
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