Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Health https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Some mutations in COVID-19 may reduce the effectiveness of the vaccine

Some mutations in COVID-19 may reduce the effectiveness of the vaccine



Scientists report alarming signs that some recent mutations in the virus that causes COVID-19 may moderately limit the effectiveness of two current vaccines, although they stress that shots still protect against the disease.

Researchers expressed concern Wednesday about the preliminary findings, largely because they speculate that 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 researchers from the National Institutes of Health and elsewhere.

Another, more limited study on Wednesday gave encouraging news about the protection of a vaccine against some of the mutations.

One way vaccines work is to stimulate the immune system to produce antibodies that block the virus from infecting cells. The Rockefeller researchers took blood samples from 20 people who received the Moderna or Pfizer vaccine and tested their antibodies against various viral mutations in the laboratory.

In some, the antibodies did not work well against the virus ̵

1; the activity was up to three times less depending on the mutation, said the study’s lead author, Dr. Rockefeller, Michelle Nusenzweig.

“It’s a small difference, but it’s definitely a difference,” he said. The antibody response is “not so good” when the virus is blocked.

Earlier studies found that both vaccines were about 95% effective in preventing COVID-19 disease.

The latest findings were published late Tuesday on an online website for researchers and have not yet been published in a journal or reviewed by other scientists. Nusenzweig is paid for by the Howard Hughes Medical Institute, which also supports scientific coverage in The Associated Press. The university has applied for a patent related to his work.

The coronavirus is growing more genetically, and scientists say the high incidence of new cases is the main cause. Each new infection gives the virus a chance to mutate while making copies of itself.

The latest variants or versions of the virus, which have appeared in Britain, South Africa and Brazil, appear to be spreading more easily, and scientists say it will lead to more cases, deaths and hospitalizations. The new variants do not appear to cause more serious disease, but their ability to ultimately undermine vaccines is a problem.

E. John Wery, an immunology expert at the University of Pennsylvania, said Rockefeller scientists were “among the best in the world” in this work and their results were worrying.

“We don’t want people to think that the current vaccine is outdated. That is absolutely not true, “he said. “There’s still immunity here … a good level of protection,” but mutations “actually reduce how well our immune response recognizes the virus.”

The news comes at a “really important moment 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 release 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’s going to be a slow evolution. We will have to have tools that are slowly evolving with it, “such as treatments that offer combinations of antibodies, not one,” he said.

Dr. Drew Weissman, a scientist at the University of Pennsylvania whose work helped produce the Moderna and Pfizer vaccines, said the findings of the antibodies were disturbing, but noted that the vaccines also protected in other ways, such as stimulating reactions from others. parts of the immune system. The new job involves only 20 people and not a huge range of ages or races, “and it all matters” about how generalizing the results are, he said.

On Wednesday, Pfizer and its German partner BioNTech announced a second round of reassuring findings about their vaccine against one of the options.

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 Britain and South Africa. Similarly, there was no sign of problems when testing some additional mutations.

The latest work tests all mutations from the UK variant at once, not one at a time. Tests from 16 vaccine recipients 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 chief scientific officer, Dr. Philip Dormitzer, said earlier that the next steps included testing the vaccine against additional mutations found in the South African variant.

Moderna and AstraZeneca, which produce a different type of COVID-19 vaccine used in some countries, are also testing how their vaccines resist different mutations.

If the virus eventually mutates enough that the vaccine needs to be corrected – similar to how flu vaccines change over most years – changing the prescription would not be difficult for vaccines made with newer technologies. Both Pfizer and Moderna vaccines are made with a part of the genetic code of the virus that is easy to change.

“It is desirable to think that first-generation vaccines will suffice or that vaccines will solve our problems on their own,” said Mayo Clinic vaccine expert Dr. Gregory Poland.

“We are shooting ourselves in the foot by allowing this virus to be transmitted without any problems,” and we are not doing “common sense” measures such as wearing masks, as some other countries do, he said.

“How can bars and restaurants be full?” It’s like “what kind of pandemic?” We reaped the seeds we sowed, “he said.

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Medical writer Lauran Neergaard contributes with reporting.

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The Associated Press’s Department of Health and Science receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.


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