Scientists report worrying signs that some recent mutations in the virus causing COVID-19 may modestly slow down the effectiveness of two current vaccines, although they stress that the traits still protect against the disease.
Researchers expressed concern Wednesday over preliminary findings, in large part because they suggest future mutations could undermine vaccines. The research tested coronaviruses in the UK, South Africa and Brazil, and was conducted by Rockefeller University in New York with scientists from the National Institutes of Health and elsewhere.
A different and more limited study on Wednesday gave encouraging news about protecting a vaccine against some of the mutations.
One way vaccines work is to encourage the immune system to produce antibodies that block the virus from the cell infection. Rockefeller researchers obtained blood samples from 20 people who had received the Modern or Pfizer vaccine and tested their antibodies against several mutations of the virus in the lab.
With some, the antibodies did not work so well against the virus: activity ranges from three to three less, depending on the mutation, said study leader Dr. Michel Nussenzweig of Rockefeller.
“It’s a small difference, but it’s definitely a difference,” he said. The response of the antibodies “is not so good” to block the virus.
Previous research has established that both vaccines are approximately 95% effective in preventing COVID-19 disease.
The latest findings were published Tuesday afternoon on an online website for researchers and have not yet been published in a journal or reviewed by other scientists. Nussenzweig is paid for by the Howard Hughes Medical Institute, which also supports scientific coverage at The Associated Press. The university has applied for a patent related to his work.
The coronavirus has been growing more 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 as it makes copies of it.
Recent variants or versions of the virus that emerged 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 new variants do not appear to cause more serious illnesses, but their ability to end vaccines is a concern.
E. John Wherry, an immunology expert at the University of Pennsylvania, said Rockefeller scientists are “among the best in the world” in this work and their results are worrisome.
“We do not want people to think that the current vaccine is obsolete. That’s not absolutely true, “he said.” There’s still immunity here … a good level of protection, “but the mutations” actually reduce the degree to which our immune response recognizes the virus. “
The news comes at “a really important time in the pandemic,” said Dr. Buddy Creech, a vaccine specialist at Vanderbilt University.
“We have an arms race between vaccines and the virus. The slower we spread the vaccine around the world, the more opportunities we give this virus to escape, ”and develop mutations, he said.
Dr. Matthew Woodruff, an immunology researcher at Emory University, agreed.
“It will be a kind of slow evolution. We will have to have tools that develop slowly,” such as treatments that offer combinations of antibodies instead of one.
Dr. Drew Weissman, a scientist at the University of Pennsylvania whose work helped lead to the Modern and Pfizer vaccines, said antibody findings are worrisome, but noted that vaccines also protect in other ways. , such as stimulating responses from other parts of the immune system. The new work involved only 20 people and not a lot of ages or races, “and it all matters” in generalizing the results, he said.
On Wednesday, Pfizer and its German partner BioNTech reported a second round of reassuring findings about their vaccine against one of the variants.
Earlier this month, Pfizer and researchers at the University of Texas Medical Branch said the vaccine was still effective against a mutation called N501Y from new variants found in the UK and South Africa. Similarly, there were no signs of problems when they tested some additional mutations.
The last work tested all mutations of the UK variant at once not one by one. Trials of 16 vaccine receptors showed no significant difference in the ability of antibodies to block the virus, the researchers said in a report t.
Pfizer did not immediately comment on Rockefeller’s findings, but his chief scientist, Dr Philip Dormitzer, said earlier that the next steps include testing the vaccine against additional mutations found in the South African variant.
Moderna and AstraZeneca, which manufacture a different type of COVID-19 vaccine used in some countries, have also been testing how their vaccines withstand different mutations.
If the virus eventually mutates enough for the vaccine to adjust, just as flu vaccines are altered most years, it would not be difficult to modify the prescription for vaccines made with newer technologies. Both the Pfizer and Modern vaccines are made with a fragment of the genetic code of the virus that is easy to change.
Said Dr. Gregory Poland, a vaccine expert at the Mayo Clinic, who is “excited” to believe that first-generation vaccines will suffice or that only vaccines will solve our problems.
“We are shooting ourselves in the foot allowing unrestricted transmission of this virus” and we are not taking “common sense” measures such as forcing us to wear masks as some other countries are doing, he said.
“How can bars and restaurants be filled? It’s like “what pandemic?” We have harvested the seeds we have sown, ”he said.
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Medical writer Lauran Neergaard contributed the information.
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The Associated Press Health and Science Department is supported by the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.