The FDA is working on whether to change the COVID vaccine for the fall

US health authorities are facing significant decisions. Whether to offer a new COVID-19 booster shot this fall that has been modified to better match the latest coronavirus variants.

modern When Pfizer Tested updated shots against the hyperinfectious Omicron mutant and served as an advisor to the Food and Drug Administration. Discuss Is it time to switch to Tuesday? The decision to do so may set the stage for similar movements by other countries.

“This is the most difficult science,” said the FDA Vaccine Officer. Dr. Peter MarkesHe added that a final decision is expected within a few days of the advisory board’s recommendations.

Current COVID-19 vaccine Saved millions of lives around the world According to modeling studies, just in the first year of use. Preliminary research also shows that Moderna and Pfizer shots provide strong protection against the worst consequences (severe illness and death). Especially after booster immunization..

However, these vaccines target the original coronavirus strain and provide protection against infection between weakened immunity and constant barrage of mutants. Remarkably fell.. The challenge is to determine if a fine-tuned booster is likely to blunt another surge if there is no way to predict which variant will be the main threat.

In an analysis prepared for Tuesday’s meeting, FDA officials admitted that targeting last winter’s version of Omicron is “slightly outdated” as it has already been replaced by that version. rice field In addition, infectious relatives.

“We obviously want to get it right enough,” Marks said.

Many experts say that updated boosters promise at least a little more profit.

Epidemiologists say it is “more likely to be useful” than simply adding an additional dose of today’s vaccine. William Hanage Harvard TH Chan Public Health School.

This assumes that the virus will not throw another curve ball.

“It’s very annoying because we’re following rather than moving forward, so we couldn’t come up with a better variant-proof vaccine,” he said. Dr. Eric TopolHe is responsible for the Scripps Research Translational Institute and encourages the government to drive the next generation of shots.

In addition to concerns about the winter COVID-19 wave, it is About half of Americans It was never the subject of that very important first booster dose. The updated version may seduce some of them.

But he said, “We need to change our expectations.” Dr. William Moss Members of the Johns Hopkins Bloomberg School of Public Health said early studies of the pandemic created unrealistic hopes of stopping even the mildest infections. “Our strategy does not allow booster immunization every few months or even every six months to prevent infection.”

The best candidates are what scientists call “divalent” shots. This is a combination of the original vaccine and Omicron protection.

According to immunologists at the University of Pennsylvania, the original vaccine has proven effective against severe diseases and is an antibody that fights at least some viruses that are strong enough to cross-reactive with new variants. Because it promotes the production of. E. John Welly..

“It’s very important to be able to push the boost response a bit in one or the other direction without losing the core,” he said.

Moderna and Pfizer have found that combo shots significantly increase the level of antibodies that fight Omicron in adults who have already been vaccinated three times, rather than just three routine doses.

Recipients have also developed antibodies that can fight the latest relatives of the named Omicron. BA.4 and BA.5, Not so many. It is not clear how much protection will be converted for how long.

Antibodies are an important first layer of defense formed after vaccination or prior infection.They can prevent infection by recognizing peplomers on the outer coating of coronavirus Block the invasion of cells..

However, the antibodies spontaneously decline and each new variant comes with a different-looking peplomer, making it more likely that detection by the remaining antibodies can be avoided. According to another study published this month in Nature and the New England Journal of Medicine, the latest Omicron relatives dodge antibodies in both vaccinated and those who have recovered from the infection caused by the original Omicron strain. Is even better.

Its first booster people are supposed to get enhanced immunological memory and help explain why hospitalization and protection against death prove to be more durable.Various defenders called T cells when the virus sneaks through past antibodies Spring actionAttack infected cells to control the disease.

“T cells recognize the virus in a radically different way,” he said, rather than looking for spoofed peplomers, but for parts of the virus that haven’t changed much.

Still, as people grow older, all parts of the immune system gradually weaken. There is little data on how long T cell protection against COVID-19 lasts, or how it is altered by different mutants and vaccines.

Wherry and dozens of other scientists have recently urged the FDA to stop focusing solely on antibodies and begin measuring T cells when deciding on a vaccination strategy.

Biden administration revealed it Need Congress to provide more money If the FDA clears the updated booster, the government can buy enough for all Americans who want it.

Also, the government’s top infectious disease expert, Dr. Anthony Fauci, told Congress last week that a better next-generation vaccine, including a nasal version that could better block nasal infections and more variability-resistant shots. He said more research funding is important to create.

“The virus is changing and we need to catch up with it,” Fauci said.