COVID vaccines for children under five receive the green light from regulators

Children under the age of five have just become the last age group eligible for the COVID vaccine in the United States

The Advisory Committee of the Food and Drug Administration voted 21 to 0 in favor of authorizing the Pfizer-BioNTech vaccine for children aged six months to four years and authorizing the Moderna vaccine for those aged six months to five years. The decision by the FDA’s Advisory Committee on Vaccines and Related Organic Products reflects the panel’s consensus among health experts that the benefits of vaccines outweigh the risks to young children.

The FDA concluded, based on its own analysis, that both Modern and of Pfizer vaccines are safe for these age groups and meet the criteria for efficacy based on their immune response. If the agency follows the recommendations of the advisory committee, as it usually does, and the U.S. Centers for Disease Control and Prevention recommends vaccines, they may be available to these children soon after.

“It was an important day for parents who want to know they have another way to protect their child,” said Paul Ofit, a member of the FDA’s Advisory Committee on Vaccines who is director of the Vaccine Training Center and a physician in the ward. on infectious diseases. diseases at the Children’s Hospital of Philadelphia. He likens waiting for young children for the vaccine to a scene from the movie Jaws, in which the protagonist describes a group of sailors from the Navy, trapped in waters full of sharks and waiting to be rescued by helicopter. “The most difficult moment was when helicopters were there, rescuing people, waiting your turn, “said Ofit, paraphrasing line.

“As pediatricians, the opportunity to offer this life-saving innovation to our patients comes first,” said Sally Permar, chair of pediatrics at Weill Cornell Medicine and chief pediatrician at Presbyterian Comani Children’s Hospital in New York City. “Not only do you protect your child from the rare chance of having a serious illness, but you also help him achieve the normalcy in life we ​​all seek – to maintain all his current activities without interruption.”

For many parents, the news came as a welcome relief. “I’ve been waiting for years for this day to come, and I’m so grateful to everyone who worked tirelessly to make the world a little safer for these kids,” said Megan Morris, a parent of a two-year-old boy in Brooklyn, New York. vaccines are unlikely to completely prevent her son from contracting COVID, but “this will give him some level of protection and, I hope, allow him to start living the childhood I had hoped for.”

The first COVID vaccines received an Adult Emergency Authority (EUA) for adults in December 2020, and the EUA for the Pfizer vaccine was later changed to include people aged 16 and over. The Pfizer vaccine was given to 12- to 15-year-olds in May 2021 and to five- to 11-year-olds last October. The youngest children had to wait the longest.

Although COVID is less likely to cause severe illness in children than in adults, the fact remains that by 2 June, 442 children under five died of the disease in the United States (for comparison, flu killed 87 children in this age group in the 2019-2020 season.) And many more children have been hospitalized with COVID, especially during the recent Omicron jump. Children can develop a condition known as multisystemic inflammatory syndrome in children (MIS-C), which causes inflammation in organs including the heart, lungs, kidneys and brain. And as adults, children can suffer from prolonged COVID.

Testing a new vaccine in children is always a challenge: the required safety threshold is higher in a population of individuals who are still developing and generally healthy. In addition, the elderly are at greatest risk of serious illness and death from COVID. So when the vaccines were developed, it made sense to start testing them in the last age group first.

“We worked our way down,” Ofit said. The majority of COVID deaths occurred in the elderly, so health experts wanted to make sure that people in this age group received the vaccines first. They were then evaluated in young adults, then five to 11-year-olds, and finally those under five. “Parents can at least feel pretty confident that you have billions of doses that have been there,” he says. “So you have a lot of information at the moment about these vaccines.”

Because young children have a relatively low risk of developing severe COVID, manufacturers and regulators wanted to make sure the vaccine did not cause side effects that were more dangerous than the disease itself. For children under the age of five, Pfizer initially tested two child-specific doses of its vaccine, one tenth of the adult dose, but this did not lead to a strong enough immune response, so a third dose was added. Moderna is testing two doses of its vaccine in children under the age of six, each a quarter of the adult dose.

Safety

Children in the Pfizer and Moderna vaccine trials had mild to moderate side effects – most commonly pain and redness at the injection site, headache, fatigue, irritability and fever. All were milder and less common than in older children and adults, with the exception of fever, which is particularly alarming in infants because it can cause seizures. Very few of the participants in the trial did have a seizure or other adverse event, but most of them were considered unrelated to the vaccine.

There were no cases of myocarditis or pericarditis (inflammation of the heart muscle or its lining) in children aged six months to four or five years in any of the relevant studies. Rare cases of vaccine-induced myocarditis or pericarditis have been reported in older adolescents and young adults, mostly men, but these cases have generally been resolved on their own. COVID and other infections can also cause such inflammation and are usually more severe than those associated with vaccines. There were no deaths among children in the experiments.

Efficiency

Both Pfizer and Moderna vaccines produce immune responses that meet FDA criteria for approval in young children. Their effectiveness was assessed by so-called immunomodification – essentially comparing the levels of antibodies caused by the vaccine that neutralize the virus that causes COVID in young children with the levels in young adults.

In a preliminary analysis in children under five years of age, three doses of Pfizer vaccine had an apparent efficacy of 80.4 percent in preventing confirmed COVID (75.6 percent in children aged six to 23 months and 82.4 percent in children aged 6 to 23 months). two to four years). old men). Moderna’s two-dose vaccine has an apparent efficacy of 50.6% in children aged six to 23 months and 36.8% among those aged two to five years. Many members of the FDA’s advisory committee said during Wednesday’s meeting that the number of children in the trials, however, was too small to draw firm conclusions about these levels of efficiency.

Although these levels of efficacy are lower than those seen in older children and adults, it should be noted that vaccine trials in young children were conducted when the relatively recent version of Omicron, which is known to be partially avoids immunity from vaccination or previous infection, has already been circulating.

“The big difference here is that the virus has changed,” says Permar. “The virus circulating now is the Omicron variant, which we know is more transmissible than any of the other variants and can avoid the immunity against the vaccine that was caused by the original vaccine. The effectiveness of the vaccines in young children is in line with real data for adults with the Omicron variant, she said. “Something like the game changed when the tests were done on the youngest children,” she added.

Kausar Talaat, an associate professor of international health at the Johns Hopkins Bloomberg School of Public Health and a researcher in the Pfizer vaccine study in children, agrees. “It’s probably unfair to compare … this vaccine tested in young children during the Omicron period with the same vaccine tested in adults,” she said.

Vaccines continue to provide good protection against serious illness, hospitalization and death in adults and are expected to provide similar protection in children.

For young children, there are now two vaccines with very similar mechanisms, but different doses, dosing intervals and efficacy. Talaat says she is curious to see if the CDC will recommend one vaccine over another. “I prefer my children to have one that is more effective, even if it takes longer,” she said, “but it’s a conversation that people should have with their pediatricians if we’re lucky enough to have a choice.”

Relief and disappointment

Many parents are extremely eager to vaccinate their babies and young children. The great emotion among many of those with whom American American spoke was relief, followed by disappointment that the resolution took so long.

Fred Blau of Brooklyn has a five-year-old daughter and a three-year-old son. He and his wife “are both very vaccinated,” he said. “We hoped to vaccinate our children in the autumn or winter of 2021, or maybe in January” this year, but “we waited and waited and waited.” Although his son has COVID, Blau still sees the benefit of vaccinating him. “Although young children tend to have the slightest illness, there are still risks and we would like to mitigate them as much as possible and feel comfortable returning to our normal lives as much as possible,” Blau said. .

Sarah Trist of Albany, California, has a 22-month-old daughter and a five-year-old son. She works in the Auckland Head Start program, a training program for young children, and has seen first-hand how COVID can break into a day center. “Every day I wait for the call from the kindergarten that my child is in quarantine,” she said. When the vaccines first came out, she was very hopeful, “but the finish line just kept moving,” one delay after another. Now that the day is finally here, I feel “really bitter,” says Trist.

“The main feeling is relief,” said Alison Moy, a parent of a 20-month-old boy in Pittsburgh. “After the vaccines appeared for adults and older children, many people returned to normal life,” added Moi, who works as a microbiologist. “But that wasn’t an option for us because we had to think about our child.” When her son’s pediatrician emailed her parents to allow them to schedule vaccination appointments before the permit was announced, Moi called and made an appointment immediately. When staff offered a choice between Pfizer or Moderna, she told them, “I don’t care!”

However, not all parents are so enthusiastic. Less than 60 percent of children and adolescents in the United States between the ages of 12 and 17 have been fully vaccinated, and less than one-third of those aged five to 11 have been vaccinated. In a survey by the Kaiser Family Foundation, only for one in five parents of children under five they said they wanted to vaccinate their child “immediately”, and two out of five said they wanted to “wait and see” how the vaccine worked. Nearly 30 percent of parents with children of this age say they “definitely won’t” vaccinate their child at all.

“As long as people do not perceive this as a significant infection in children, especially young children, they are unlikely to vaccinate their child,” Talaat said. Permar agrees: “Inadvertently, leaving the youngest children in the trials shows parents that this is not so necessary,” she said. Scientists need to rethink how they conduct clinical trials in children, Permar added. Although it is important to do the first research on new medical products in agreeable adults, young children should be involved earlier in the process, she said.

However, for parents such as Trist, vaccine safety data are sufficient. Any risk of the vaccine is “lower than the risk of COVID,” she says, and “this is a very clear choice to make.”