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Scientists are reporting disturbing signs that some recent mutations in the virus that causes COVID-19 could moderately limit the effectiveness of two current vaccines, although they point out that the vaccines still protect against the disease.
The researchers expressed concern Wednesday over the preliminary results, largely because they suggest that future mutations could harm the vaccines. The research tested for coronaviruses from the United Kingdom, South Africa and Brazil, and was led by Rockefeller University in New York with scientists from the National Institutes of Health and elsewhere.
A different and more limited study on Wednesday yielded encouraging news about a vaccine’s protection against some of the mutations.
One of the ways that vaccines work is by causing the immune system to make antibodies that prevent the virus from infecting cells. Rockefeller researchers obtained blood samples from 20 people who had received the Moderna or Pfizer vaccine and tested their antibodies against various viral mutations in the lab.
With some, the antibodies did not work as well against the virus – the activity was one to three times less, depending on the mutation, said study leader Dr Michel Nussenzweig of Rockefeller.
“It’s a little difference, but it’s definitely a difference,” he said. The antibody response is “not as good” at blocking the virus.
Previous research has established that both vaccines are about 95% effective in preventing COVID-19 disease.
The latest findings were published Tuesday night on an online website for researchers and have yet to be published in a journal or reviewed by other scientists. Nussenzweig is paid by the Howard Hughes Medical Institute, which also provides science coverage for the Associated Press. The university applied for a patent related to his work.
The coronavirus is increasingly genetically diverse, and scientists say the high rate of new cases is the main reason. Each new infection gives the virus a chance to mutate by copying itself.
Recent variants or versions of the virus that have appeared in the UK, South Africa and Brazil appear to be spreading more easily and scientists say this will lead to more cases, deaths and hospitalizations. The newer variants do not appear to cause more serious illness, but there is concern about their ability to eventually cut back on vaccines.
E. John Wherry, an immunology expert at the University of Pennsylvania, said the Rockefeller scientists are “among the best in the world” at this work and their results are cause for concern.
“We don’t want people to think that the current vaccine is already outdated. This is absolutely not true, ”he said. “There’s still immunity here … a good level of protection,” but the mutations “actually reduce the ability of our immune response to recognize the virus.”
The news comes at “a really important time in the pandemic,” said Dr Buddy Creech, vaccine specialist at Vanderbilt University,
“We have an arms race between vaccines and the virus. The slower we deploy the vaccine around the world, the more opportunities we give for this virus to escape ”and develop mutations, he said.
Dr. Matthew Woodruff, an immunology researcher at Emory University, agreed.
“It’s going to be a kind of slow evolutionary march. We’re going to have to have tools that slowly evolve with it, ”like treatments that offer combinations of antibodies rather than just one, he said.
Dr Drew Weissman, a University of Pennsylvania scientist whose work contributed to the development of Moderna and Pfizer vaccines, said the antibody findings are concerning, but noted that the vaccines also protect by d ‘other means, for example by stimulating responses from other parts of the immune system. The new work only involved 20 people and not a wide range of ages or races, “and that all counts” in the generalization of the results, he said.
On Wednesday, Pfizer and its German partner BioNTech reported a second round of reassuring findings about its vaccine against one of the variants.
Earlier this month, Pfizer and researchers at the University of Texas medical branch said the vaccine remains effective against a mutation called N501Y from new variants found in the UK and South Africa. Likewise, there was no sign of a problem when they tested for additional mutations.
The latest work tested all of the UK variant mutations at once rather than one at a time. Tests performed on 16 vaccinees did not show much difference in the ability of antibodies to block the virus, the researchers said in a report.
Pfizer did not immediately comment on Rockefeller’s findings, but its scientific director, Dr Philip Dormitzer, had previously said next steps include testing the vaccine against additional mutations found in the South African variant.
Moderna and AstraZeneca, which make a different type of COVID-19 vaccine used in some countries, have also tested their vaccines for resistance to different mutations.
If the virus mutates enough that the vaccine has to be adjusted – just as influenza vaccines are changed in most years – it wouldn’t be difficult to change the recipe for vaccines made with newer technology. Both Pfizer and Moderna vaccines are made with a piece of the virus’s genetic code that is easy to change.
It is “wishful thinking” to believe that first-generation vaccines will suffice, or that vaccines alone will solve our problems, said Dr Gregory Poland, vaccine expert at the Mayo Clinic.
“We are shooting ourselves in the foot by allowing unhindered transmission of this virus” and by not taking “common sense” measures such as requiring a mask like some other countries do, he said. -he says.
“How can bars and restaurants be full? It’s like “what pandemic?” We harvested the seeds that we sowed, ”he said.
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Medical writer Lauran Neergaard contributed reporting.
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The Associated Press’s Department of Health and Science receives support from the Department of Science Education at the Howard Hughes Medical Institute. The AP is solely responsible for all content.
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