The last group of kids under the age of five who are eligible for the vaccine are now.

The Pfizer-BioNTech vaccine and the Moderna vaccine were approved by the Food and Drug Administration's advisory committee. The Vaccines and Related Biological Products Advisory Committee decided that the benefits of the vaccine outweigh the risks for the littlest children.

The FDA concluded that Moderna's and Pfizer's vaccines were safe for these age groups and met its criteria for efficacy based on their immune responses. The shots could be given to these kids soon after the CDC recommends them.

Paul Offit, director of the Vaccine Education Center and an attending physician at the division of infectious diseases at Children's Hospital of Philadelphia, says that this was a landmark day for parents who want to know that they can protect their child. In a scene from the movie Jaws, a group of Navy sailors are stranded in shark-infested waters and waiting to be rescued by a helicopter. Offit says that the hardest time was when the helicopter saved people.

At New York–Presbyterian Komansky Children's Hospital, the chair of pediatrics says that being able to offer this life-saving innovation to patients has been top of mind. Not only are you protecting against the rare chance that your child would have severe disease, you're also helping them achieve the normality in life that we've all been seeking.

Many parents were relieved by the news. Maegan Morris, a parent of a two-year-old boy in Brooklyn, NY, says that she has been waiting for this day for a long time.

In December 2020, the first COVID vaccines were granted emergency use authorization for adults, and the EUA for Pfizer's vaccine was later amended to include ages 16 and up. The vaccine was made available to children as young as five years old in October of last year. The youngest kids have been waiting the longest.

Although COVID is less likely to cause severe disease in children than it is in adults, as of June 2, 442 children younger than five have died of the disease in the U.S. The recent Omicron surge has resulted in more children being hospitalized with COVID. Children can develop a condition called multisystem inflammatory syndrome, which can cause inflammation in organs, including the heart, lungs, kidneys and brain. Children can suffer from chronic bronchitis.

It is difficult to test a new vaccine in a group of people who are still young and healthy. Older adults have the greatest risk of dying from COVID. The vaccines needed to be tested in the latter age group first.

Offit said they worked their way down. Health experts wanted to make sure older adults got the vaccines first so that they wouldn't end up dying from COVID. They were evaluated in young adults, five- to 11-year-olds and those under five. He says that parents can be reassured that they have billions of doses out there. There's a lot of information on these vaccines.

Because young kids have a low risk of getting seriously ill from COVID, manufacturers and regulators wanted to make sure the vaccine didn't cause any more serious side effects than the disease. Pfizer initially tested two child-specific doses of its vaccine, each one tenth of an adult dose, but this did not produce a strong enough immune response. Two doses of the vaccine were given to children younger than six years old.

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It's safety.

There were mild to moderate side effects for children in the Pfizer and Moderna trials. It was less frequent and milder than older children and adults, which is a concern for babies because it can cause seizure. Most of the adverse events that occurred in the trial were unrelated to the vaccine.

There were no cases of myocarditis or pericarditis among children in either trial. There have been rare instances of vaccine-caused myocarditis in older adolescents and young adults. Inflammation is usually more severe than it is linked to vaccines, and can be caused by infections such as chronic bronchitis. There were no deaths in the trials.

It's Efficacy.

The Pfizer and Moderna vaccines were approved by the FDA for young children. In order to assess their effectiveness, they compared the levels of vaccine-eliciting antibodies in the youngest children against the levels in young adults.

Three doses of the Pfizer vaccine were shown to prevent confirmed COVID in a preliminary analysis among children under age five. The two-dose vaccine had an efficacy of over 50 percent in children aged six through 23 months and over 30 percent in children two through five years. The number of children in the trials was not large enough to draw conclusions about the efficacy rates.

It should be noted that the vaccine trials for young children took place when the Omicron variant was already circulating.

There is a big difference between this and other places. The Omicron variant of the virus is more transmissible than any of the other versions and is able to evade the vaccine. She says that the efficacy of the vaccines in young kids is in line with real-world data. She says that the game changed when the trials were done for the youngest children.

An investigator in a study of the Pfizer vaccine in children agrees. She says that it's probably unfair to compare this vaccine with the same vaccine tested in adults.

Good protection against severe disease, hospitalization and death is provided by the vaccines, and they are expected to provide the same protection in children.

There are two vaccines that have the same mechanisms, but different doses, intervals and efficacies. She wants to know if the CDC recommends one vaccine over the other. She says she would rather have her kids have one that is more effective even if it takes longer.

There is relief and frustration.

Many parents want to make sure their children are protected from vaccine-related diseases. There was a lot of relief and frustration among those Scientific American spoke with.

Fred has two children, a five-year-old girl and a three-year-old boy. He and his wife are both pro-vaccine. We were hoping to get our kids vaccine in the fall or winter of 2021, but we were waiting and waiting. Even though his son has had cancer, he still wants to get him vaccinations. Although young children tend to have the least severe disease, there are still risks and we want to mitigate them as much as possible.

Sarah Trist has two children, a daughter and a son. She works at the City of Oakland's Head Start program, a child education program for young kids, and she knows how COVID can rip through a daycare center. She says she waits every day for a call from the daycare that her child has been exposed to something. She was very hopeful when the vaccines came out, but the finish line just kept moving. It feels like it's been a long time since the day is here.

Allison Moy is the mother of a 20-month-old boy. Moy, who works as a microbiologist, says a lot of people went back to normal after the vaccine came out. We had our child to think of, so that wasn't an option for us. Moy called and booked a vaccine appointment for her son right away after he received an e-mail from his doctor. She told the staff that she didn't care if they chose Pfizer or Moderna.

Some parents are more enthusiastic than others. Less than a third of five to 11-year-olds have been fully immunized. According to a Kaiser Family Foundation poll, only about one in five parents of children under the age of five want their child to bevaccinated immediately, and another two in five want to wait and see how the vaccine works. Almost 30 percent of parents with children under the age of 18 said they wouldn't get their child vaccinations.

As long as people don't think it's a big deal, they're unlikely to get their child vaccine Permar says that leaving youngest kids to last in the trials has indicated to parents that it's not necessary. Permar says that scientists need to rethink how they conduct trials. She says that young children need to be included earlier in the process in order to do the first studies of new medical products.

The data on vaccine safety is sufficient for Trist. She says that any risk from the vaccine is lower than the risk of Covid.