Happy Nice Mall

The coronavirus vaccine made by Pfizer-BioNTech is much less effective at preventing infection in children ages 5 to 11 than older adolescents or adults, according to a new set of big data collected by health authorities in New York State. profound consequences for these children and their parents.

The Pfizer vaccine is the only Covid vaccine authorized for this age group in the United States. Data collected during the Omicron surge still prevent serious illness in children, but provide virtually no protection against infection, even within a month of full vaccination.

The sharp decline in vaccine performance in young children may be due to older children and adults receiving one-third of the dose given to researchers and federal officials who reviewed the data.

The findings, published online Monday, follow clinical trial results that showed the vaccine proved unsatisfactory in children aged 2 to 4 who received an even smaller dose.

Experts fear the news will further deter undecided parents from vaccinating their children. Other studies have shown that the vaccine does not provide strong protection against infection with the Omicron variant in adults either.

“This is disappointing, but not entirely surprising, considering it’s a vaccine developed in response to an earlier variant,” said Eli Rosenberg, assistant director of science in the New York State Department of Health, who led the study. “It seems very sad to see this rapid decline, but it’s all against Omicron anyway.”

Still, he and other public health experts said they recommend the vaccine to children who are protected against serious diseases, which is shown even in the new dataset.

Pediatric vaccine expert at Vanderbilt University, Dr. “We need to make sure we’re emphasizing the bun, not the hole,” said Kathryn M. Edwards.

Dr. In their study, Rosenberg and colleagues analyzed data from 852,384 newly fully vaccinated children aged 12-17 years and 365,502 children aged 5-11 years between December 13, 2021, and January 31, 2022, the height of Omicron. swell.

The effectiveness of the vaccine against hospitalization dropped from 85 percent to 73 percent in older children. In younger children, activity dropped from 100 percent to 48 percent. However, these estimates have a wide margin of error, as very few children are hospitalized.

Infection protection numbers are more reliable. Vaccination effectiveness against infection in older children dropped from 66 percent to 51 percent. But in younger children, it dropped sharply from 68 percent to 12 percent.

The numbers vary widely between the ages of 11 and 12. In the week ending January 30, the vaccine’s efficacy against infection was 67 percent in 12-year-olds and just 11 percent in 11-year-olds.

“The difference between the two age groups is striking,” said Florian Krammer, an immunologist at the Icahn School of Medicine at Mount Sinai.

The biological difference between the two years is likely to be minimal, but 12-year-olds were given 30 micrograms of the vaccine – the same dose given to adults – while 11-year-olds were given just 10 micrograms.

“This is very interesting because it shows that it is the dose that almost makes the difference,” he added. “The question is how to fix this.”

at least it has been 851 deaths due to Covid-19 in children under 17 years of age and approximately 7,000 cases Multisystem inflammatory syndrome in childrenA rare but serious condition associated with Covid. More children were hospitalized during the Omicron surge than at any point in the pandemic.

Dr. Rosenberg said the findings highlight the need to gather more information about the best dose, number and timing for vaccines given to children. They also underline that vaccinations, along with masks and social distance, are only a measure of protection from the virus.

Dr. Rosenberg’s research was published just days after the Centers for Disease Control and Prevention published it. new suggestions This would allow the majority of Americans to stop wearing masks, including in schools.

The new data also raises important questions about the Biden administration’s strategy to vaccinate children. Only one in four children aged 5 to 11 two doses of vaccine. (The CDC has yet to recommend booster doses for this age group.)

The vaccine is not yet approved for children younger than 5 years old. While the Food and Drug Administration’s scientific advisors were scheduled to meet on February 15 to evaluate two doses of the vaccine for the youngest children, three doses were still being tested. However, the meeting was delayed after Pfizer presented additional data showing that the two doses were not strongly protective against the Omicron variant of the virus.

Dr. Rosenberg, with his findings in early February, said the agency’s director, Dr. He briefed senior CDC officials, including Rochelle P. Walensky. FDA leaders learned of the data around the same time. Some federal scientists pressed for the data to be made public before the FDA expert meeting scheduled for Feb. 15, and they saw it as highly relevant to the dosing debate in children under the age of 5, with federal officials and others familiar with their responses to it.

The data are generally consistent with: report from the UK It shows that vaccine efficacy against symptomatic infection in adolescents aged 12 to 17 years dropped to 23 percent after two months. The CDC is compiling its own data on the effectiveness of the vaccine in young children and is expected to release at least some of it as early as this week, according to people familiar with the agency’s plans.

Israeli researchers have also been evaluating its performance in young children since the country made the vaccine available in November.

“We continue to review and evaluate real-world data from vaccines,” Pfizer spokesperson Amy Rose said in response to questions about the new data.

Recently retired from the FDA as senior vaccine regulator, Dr. Philip Krause said that assumptions that certain antibody levels predict vaccine efficacy should be reassessed in light of the new results.

“It definitely weakens the argument that mandates that people take lower doses,” he said.

It’s not uncommon for experts to reconsider the dosing and spacing of pediatric vaccines as more evidence becomes available. In this case, however, giving children a higher dose to initiate the immune response may not be an option, as some data suggest that too much can cause a fever, an unwanted and potentially dangerous side effect in young children.

Deepta Bhattacharya, an immunologist at the University of Arizona, said there are other alternatives that can boost immunity in young children.

Pfizer and BioNTech are testing a third dose in children under 5 years old and children 5 to 11 years old, with the idea that, as in adults, an extra vaccine can significantly boost immunity. Results from these trials are expected within a few weeks. Research in adults shows that three doses of the vaccine are more protective against the Omicron variant than two doses.

Dr. Based on studies suggesting that a longer interval between doses may improve protection, Bhattacharya said, instead of the currently recommended three doses for him and his wife’s 8- and 10-year-old children, he interrupted two doses eight weeks apart. CDC last week Encouraged some people over 12especially boys and men aged 12 to 39, waiting eight weeks between the first and second shot.

Another option would be to have a version of the vaccine designed to block the Omicron variant, or a mix of several variants. Pfizer-BioNTech, Moderna, and Johnson and Johnson are testing Omicron-specific versions of their vaccines.

The next variant may differ drastically from Omicron, as Omicron did from the Delta variant. But training the body to recognize multiple versions will still offer a better chance at preventing infection with newer forms of the virus. Dr. “Deciding when and how best to update these vaccines, I think that’s the key conversation that’s still going on here,” Bhattacharya said.

Newer vaccines that use different approaches than those currently allowed in the United States may also work better for children. A protein-based vaccine made by Novavax is under review at the FDA, and pharmaceutical companies Sanofi and GSK said this month they plan to submit their vaccines for evaluation soon.

Many parents want to vaccinate their children to prevent them from spreading the virus to their vulnerable relatives, to keep them in school, or to avoid the possibility of prolonged Covid; a persistent set of poorly understood symptoms that can occur even after a mild infection. Experts agreed that the low efficacy of the vaccine against infection did not alleviate these concerns.

Still, the vaccines “offer more protection than we thought,” said Jessica Andriesen, a vaccine data scientist at the Fred Hutchinson Cancer Research Center in Seattle.

“They can also ensure that your child who brings home Covid is not as contagious as without the vaccine, and it can also be for a shorter period of time,” he said.

The virus is persistent, and children’s risk of serious consequences increases with age. That’s why it’s a good idea to vaccinate kids early, said Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Philadelphia and FDA advisor.

“The argument I make to parents when I talk to them about this vaccine is that your kids are going to grow up,” he said. “They will need to be protected against this virus for years.”

Sharon LaFraniere and Isabel Kershner contributed to the reporting.