[Originally published: Oct. 25, 2021. Updated: May 20, 2022]
Note: Information in this article was accurate at the time of original publication. Because information about COVID-19 changes rapidly, we encourage you to visit the websites of the Centers for Disease Control & Prevention (CDC), World Health Organization (WHO), and your state and local government for the latest information.
The Centers for Disease Control and Prevention (CDC) recommends Pfizer-BioNTech’s COVID-19 vaccine for children ages 5 to 11, offering millions of children—and their parents—a greater sense of normalcy.
Distribution of pediatric doses of the vaccine began in October to thousands of pediatrician offices, pharmacies, and health centers.
The vaccine is under an emergency use authorization (EUA), which the Food and Drug Administration (FDA) grants to products during public health emergencies. Children ages 12 to 17 are already eligible for the Pfizer vaccine; Moderna is authorized for 17 and up; and Johnson & Johnson is authorized for 18 and older. Additionally, the FDA and CDC have authorized and recommended the Pfizer booster for ages 5 and up at least five months after their primary two-dose series.
There are about 28 million children between ages 5 and 11 in the United States, well above the 17 million children between ages 12 to 17 who became eligible for the Pfizer vaccine in May 2021.
Medical experts hope approval for this age group will spur more parents to have their eligible children get the shots—something that benefits the community at large.
“In addition to protecting children from COVID-19, this offers another layer of protection to close family members and contacts who may have immune problems or who may be at higher risk for severe complications of the disease,” says Thomas Murray, MD, PhD, a Yale Medicine pediatric infectious diseases specialist.
A long-awaited decision
This decision came at a pivotal moment in the pandemic, when schools reopened and the highly contagious Delta variant remained a threat. Now, the Omicron variant is dominant.
Since the start of the pandemic, more than 12 million children have tested positive for COVID-19 and more than 4.2 million new cases were recorded since the start of January, according to a report filed Feb. 3. For that week, there were more than 632,000 new cases, down from a peak of 1.2 million for the week ending Jan. 20, but still double the peak level seen in January 2021.
While only a small number of young children develop severe COVID-19 or die from the disease, the numbers are still worrisome, experts say.
“In general, younger kids do not get as sick as adults. But, throughout the course of the pandemic, we have had a number of children in our intensive care unit from COVID-related complications,” says Dr. Murray. “If we can prevent those, that is a huge win.”
And with kids back in classrooms, parents are often wondering if a case of the sniffles is seasonal allergies, a cold, flu, or COVID-19.
“We are seeing many cases of respiratory viruses right now, including younger children who are hospitalized with those viruses. Taking COVID off the table as a potential diagnosis would help immensely,” Dr. Murray says.
Vaccination also, Dr. Murray adds, allows children to return to regular activities with less risk.
“That includes indoor dining and more activities with other children,” he says. “The more children we get vaccinated, the faster we can all return to normal activities.”
Still, many parents have questions and concerns about the safety of the vaccine and how it was tested in this age group. Below, Dr. Murray and Leslie Sude, MD, a Yale Medicine pediatrician, discuss some of these issues.
Is the vaccine safe for kids ages 5 to 11?
Pfizer’s trial originally included 2,268 children. Two-thirds of the participants received two doses of the vaccine three weeks apart; one-third received two injections of a saline placebo.
According to Pfizer’s data for this group, the vaccine was 90.7% effective in preventing symptomatic COVID-19 and participants experienced a robust mounting of antibodies—similar to the levels seen in vaccinated 16- to 25-year-olds. (This trial occurred prior to the emergence of the highly contagious Omicron variant.)
In July, federal regulators asked Pfizer (and Moderna) to expand their trial sizes for this age group as a precautionary step to better detect any rare side effects from vaccination. Pfizer increased its study to about 4,500 children.
The additional children have been studied for a shorter amount of time. Still, according to Pfizer, the vaccine is safe and well-tolerated in both groups with no cases of severe illness or heart conditions.
The FDA evaluated the safety and efficacy of Pfizer’s vaccine for younger children, saying that the benefits of preventing severe cases of COVID-19 with the Pfizer vaccine generally outweighed the risks of the possible side effects in that age group.
In late February, data from the CDC and a study (not yet peer-reviewed) from the New York State Health Department showed that protection from coronavirus infection in children 5- to 11-years old waned over time, although the vaccine continued to offer protection against hospitalization and death, even during the Omicron surge.
Is the vaccine dosage for younger kids different than for teens and adults?
Yes. Children in Pfizer’s 5-to-11-year-old group received two 10-microgram doses. Teens and adults, by comparison, received two 30-microgram doses. Pfizer says its data shows that the smaller dose produces a strong immune response in the 5-to-11-year-old cohort, on par with 16- to 25-year-olds, who received a higher dose.
A smaller dose works just as well in children because their immune systems are more robust than those of adults, Dr. Sude explains.
Are the side effects from Pfizer’s vaccine different in children than in adolescents?
The side effects for children from this clinical trial are comparable to those from the adolescent study. According to the FDA, the most commonly reported side effects in the adolescent trial were pain at the injection site, fatigue, headache, chills, muscle pain, fever, and joint pain. If they arise, side effects generally are gone within one to three days.
What's more, according to documents Pfizer presented to the FDA, fever, fatigue, headache, chills, and muscle pain were generally milder and less frequent in 5- to 11- year olds than they were in adolescents.
It’s important to note that allergies to Pfizer’s vaccine ingredients are rare. (Find a full list here.) The vaccine does not contain eggs, preservatives, or latex. If you have any questions about allergies, talk to your child’s pediatrician before vaccination.
Though uncommon, the Pfizer and Moderna vaccines in some individuals—particularly in males ages 16 to 29—have been linked to an increased risk of myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the lining outside the heart).
In most cases, symptoms (chest pain, shortness of breath, feelings of a fast-beating heart) appeared within a few days of the second dose. With medical attention, including medication and rest, most felt better quickly, according to the CDC.
“I can say that in the adolescent group, these conditions are very, very rare,” Dr. Murray says. “And for children ages 5 to 11 in this trial, the dose is one-third of what was given to the older population.”
Is it safe to give children a new vaccine?
Millions of people in the U.S. have received COVID-19 vaccines “under the most intense safety monitoring in the country’s history,” the CDC says. And although the COVID-19 vaccines are new, the mRNA technology used in Pfizer’s and Moderna’s vaccines has been studied for about 15 years.
What scientists know is that mRNA molecules occur naturally in humans, and the molecules from the vaccine are destroyed and don’t stay in the body. This means they are safe for growing bodies and should not affect puberty, fertility, or brain development, Dr. Murray says.
“We have years of experience of giving vaccines to children, and the safety record is exceedingly positive,” Dr. Murray says. “And with the millions of doses we have given in the 12 and older group thus far, it has proven to be a very effective and safe vaccine.”
If COVID is less common and less dangerous in kids, why is a vaccine needed?
Given that COVID-19 tends to be less serious in children, some parents might wonder if their children actually need the vaccine. Yes, says Dr. Sude, noting that any new variant that can appear is one good reason.
“Because of variants such as Omicron, the number of children being infected either with or without symptoms is increasing,” Dr. Sude says. “And any time an individual is infected with the virus, they are a potential source of infection—they can spread it to a more vulnerable person, and overall help to perpetuate a cycle of infection that could lead to yet another variant.”
Simply put, from a public health standpoint, it will likely be impossible to gain sufficient control over the pandemic without including children in the vaccine program, Dr. Sude adds.
Do you need to space out the COVID vaccine from other immunizations?
According to the CDC, the COVID-19 vaccine can be given at the same time as other vaccines, including flu. Each injection will be administered at a different party of the body.
All children 6 months and older should get a flu vaccine, the CDC recommends. Most children will only need one dose of flu vaccine, but talk to your pediatrician to see if they recommend two doses.
When and where can my child receive their shot?
Children can receive vaccines in pediatric and primary care offices, at community health centers, rural health clinics, and in many pharmacies.
What about a vaccine for kids from Moderna or Johnson & Johnson?
In late October, Moderna announced that it will delay seeking an EUA for its vaccine for children ages 6 to 11 until the FDA completes a review of its adolescent EUA request.
Earlier in the month, the company said in a media release that its COVID-19 vaccine for children ages 6 to 11 is safe and produces a strong immune response. The company did not release the full data and it has not yet been published in a peer-reviewed journal.
For older children, Moderna released the data from its trial testing the vaccine in 3,732 adolescents ages 12 to 17 in May, and results were published in The New England Journal of Medicine in August. Two-thirds of the participants received two vaccine doses and there were no cases of symptomatic COVID-19.
Recently, the company said they were notified by the FDA that the agency needs more time to review recent international analyses of the risk of myocarditis in this age group after vaccination. The FDA said this review will likely not be completed before January 2022, according to Moderna officials.
Johnson & Johnson is conducting trials in children ages 12 to 17.
When will a COVID-19 vaccine be approved for children under the age of 5?
Pfizer and Moderna are both conducting studies of their vaccines in children ages 6 months to 4 years.
Pfizer officials in December said they would expand clinical trials to include a third dose of the 3-microgram vaccine for children ages 2 to 4. The two doses were well tolerated, but did not deliver as strong of an immune response as researchers would like. In February, Pfizer said it hopes to have its third-dose data in early April and to file an EUA then.
It is unclear when Moderna's preliminary results will be released.
What else do parents need to know about COVID-19 vaccines for young children?
If you have any questions about the COVID-19 vaccine for your child, Dr. Sude suggests you talk with your pediatrician as soon as possible.
Dr. Murray agrees. “Find a trusted health care provider, and have a conversation with them,” he says. “There is a lot of misinformation out there and we don’t want any of that to prevent someone from getting a vaccine.”
Kathy Katella contributed to the reporting of this story.
Note: Information provided in Yale Medicine articles is for general informational purposes only. No content in the articles should ever be used as a substitute for medical advice from your doctor or other qualified clinician. Always seek the individual advice of your health care provider with any questions you have regarding a medical condition.