Scientists report worrying signs that some recent mutations of the virus that causes COVID-19 may modestly slow the effectiveness of two current vaccines, although they emphasize that the injections still protect against the disease.
Researchers on Wednesday expressed concern about the preliminary findings, largely because they suggest future mutations could undermine vaccines. The study tested 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.
Another, more limited study, released Wednesday, brought encouraging news about one vaccine’s protection against some of the mutations.
One way vaccines work is to get the immune system to make antibodies that prevent the virus from infecting cells. The Rockefeller researchers took blood samples from 20 people who had received the Moderna or Pfizer vaccine and tested their antibodies against various virus mutations in the lab.
In some, the antibodies didn’t work as well against the virus – the activity was one-to-three-fold less depending on the mutation, said study leader, Dr. Michel Nussenzweig from Rockefeller.
“It’s a little difference, but it’s definitely a difference,” he said. The antibody response is “not very good” at blocking the virus.
Previous research found that the two vaccines are about 95% effective in preventing COVID-19 disease.
The latest findings were posted on an online website for researchers late Tuesday 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 reporting at The Associated Press. The university has applied for a patent regarding his work.
The coronavirus has become more genetically diverse, and scientists say the high number of new cases is the main reason. Each new infection allows the virus to mutate while making copies of itself.
Recent variants, or versions of the virus that showed up in the UK, South Africa and Brazil, seem to spread more easily and scientists say this will lead to more cases, deaths and hospitalizations. The new variants don’t seem to cause more serious illness, but their ability to ultimately undermine vaccines is a cause for concern.
E. John Wherry, an immunology expert at the University of Pennsylvania, said the Rockefeller scientists are “among the very best in the world” in this work and their results are alarming.
“We don’t want people to think that the current vaccine is outdated yet. That’s absolutely not 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 very important time in the pandemic,” said Dr. Buddy Creech, a vaccine specialist at Vanderbilt University,
‘We have an arms race between the vaccines and the virus. The slower we spread vaccines 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.
‘This will be a kind of slow evolution. We will need tools that develop slowly, ”such as treatments that provide combinations of antibodies instead of one, he said.
Dr. Drew Weissman, a University of Pennsylvania scientist whose work contributed to the Moderna and Pfizer vaccines, said the antibodies’ findings are concerning, but noted that vaccines protect in other ways as well, such as stimulating responses from other parts of the immune system. The new work involved only twenty people and not a huge range of ages or races, “and it all matters” in how generalizable the results are, 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 remained effective against a mutation called N501Y from new variants found in the UK and South Africa. Likewise, there were no signs of trouble testing for some additional mutations.
The latest work tested all mutations of the UK variant at once instead of one by one. Tests of 16 vaccine recipients showed no major 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 chief Scientific Officer, Dr. Philip Dormitzer, previously said that the next steps include testing the vaccine against additional mutations in the South African variant.
Moderna and AstraZeneca, which make another type of COVID-19 vaccine used in some countries, have also tested how their vaccines resist different mutations.
If the virus eventually mutates enough that the vaccine needs to be modified – just as flu shots are modified most years – adapting the recipe wouldn’t be difficult for vaccines made with newer technologies. Both the Pfizer and Moderna vaccines are made with a piece of the virus’s genetic code that can easily be switched.
It is “wishful thinking” to believe that first-generation vaccines will suffice, or that vaccines alone will solve our problems, said Mayo Clinic vaccine expert Dr. Gregory Poland.
“We are shooting ourselves in the foot by allowing an inexorable transmission of this virus” and not taking “common sense” measures, such as mandating masks, as some other countries do, he said.
“How can the bars and restaurants be packed? It’s like ‘what pandemic?’ We’ve harvested the seeds we’ve sown, ”he said.
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Medical writer Lauran Neergaard provided a report.
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The Associated Press Department of Health and Science is supported by the Science Education Department of the Howard Hughes Medical Institute. The AP is solely responsible for all content.