Scientists report worrying signs that some recent mutations in the virus that causes COVID-19 may modestly reduce the effectiveness of two current vaccines, although they point out that the shots still protect against the disease.
Researchers expressed concern on Wednesday about the preliminary findings, largely because they suggest that 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, more limited study on Wednesday provided encouraging news about protecting a vaccine against some of the mutations.
One way vaccines work is to cause the immune system to produce antibodies that block the virus from infecting the cells. Rockefeller researchers obtained blood samples from 20 people who received either the Moderna vaccine or the Pfizer vaccine and tested their antibodies against various viral mutations in the laboratory.
For some, the antibodies did not work as well against the virus – the activity was three to three times lower, depending on the mutation, said study leader Dr. Michel Nussenzweig, Rockefeller.
“It’s a small difference, but it’s definitely a difference,” he said. The antibody response “is not as good” to blocking the virus.
Previous research has established that the two vaccines are approximately 95% effective in preventing COVID-19 disease.
The latest discoveries were posted late Tuesday on an online site for researchers and have not yet been published in a journal or reviewed by other scientists. Nussenzweig is paid by the Howard Hughes Medical Institute, which also supports scientific coverage at The Associated Press. The university applied for a patent for his work.
Coronavirus has become 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 move because it makes children on its own.
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 new variants do not seem to cause more serious diseases, but their ability to ultimately reduce 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 worrying.
“We do not want people to believe that the current vaccine is already obsolete. It’s not absolutely true, “he said. “There is still immunity here … a good level of protection,” but the mutations “actually reduce how well 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 viruses. The slower we launch the vaccine around the world, the more opportunities we have for this virus to get rid of “and develop mutations,” he said.
Dr. Matthew Woodruff, a researcher in immunology at Emory University, agreed.
“It will be a kind of slow pace of evolution. We will have to have tools that develop slowly with it, “such as treatments that offer combinations of antibodies rather than one,” he said.
Dr. Drew Weissman, a University of Pennsylvania scientist whose work has helped lead to the Modern and Pfizer vaccines, said antibody findings are worrying, but noted that vaccines protect in other ways, such as stimulating from other parts of the immune system. The new paper involved only 20 people and not a wide range of ages or races, “and it all matters” in terms of generalizable results, he said.
On Wednesday, Pfizer and its German partner BioNTech reported a second round of reassuring findings about its vaccine against one variant.
Earlier this month, Pfizer and researchers at the University of Texas Medical Branch said the vaccine remained effective against a mutation called N501Y from new variants found in the UK and South Africa. Likewise, there were no signs of problems when testing some additional mutations.
The most recent paper tested all mutations in the UK version simultaneously, rather than one by one. Tests from 16 patients who received the vaccine showed no significant difference in the ability of the antibodies to block the virus, the researchers said in a report. t.
Pfizer did not immediately comment on the Rockefeller findings, but its chief scientist, Dr. Philip Dormitzer, said earlier that the next steps include testing the vaccine against additional mutations found in the South African version.
Moderna and AstraZeneca, which produce a different type of COVID-19 vaccine used in some countries, have also tested how their vaccines resist different mutations.
If the virus eventually moves enough for the vaccine to adapt – just as flu vaccines change in most years – changing the prescription would not be difficult for vaccines made with newer technologies. Both Pfizer and Moderna vaccines are made with a piece of the genetic code of the virus, which is easy to change.
It is a “wishful thinking” to believe that first-generation vaccines will suffice or that only vaccines will solve our problems, said Dr. Gregory Poland, a vaccine expert at the Mayo Clinic.
“We shoot ourselves in the foot, allowing this virus to be transmitted without restriction,” and we do not take “common sense” measures, such as imposing the wearing of masks, as other countries do, he said.
“How can bars and restaurants be full? It’s like “what pandemic?” We harvested the seeds we sowed, “he said.
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Medical writer Lauran Neergaard contributed to the report.
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The Associated Press Department of Health and Science receives support from the Howard Hughes Medical Institute’s Department of Science Education. AP is solely responsible for all content.