In June of 2022, the US Food and Drug Administration (FDA) granted emergency use authorization (EUA) of the bivalent Moderna and Pfizer-BioNTech COVID-19 vaccines for kids under 5 years old. These targeted the novel COVID-19 virus and its Omicron variant. For many, the news was long awaited—but since then some parents have been hesitant to get their child vaccinated. After all, with how quickly COVID protocols have changed, it’s only natural to still have questions and concerns. We reached out to pediatric experts and turned to medical authorities to answer the top questions parents have about the COVID vaccine for babies, toddlers and preschoolers. Keep reading for answers.

In this article:
What are the risks of COVID-19 for kids under 5?
What COVID-19 vaccines are currently available for kids under 5?
How do the updated COVID vaccines for kids under 5 work?
How effective is the COVID vaccine for kids under 5?
Is the COVID-19 vaccine safe for kids under 5?
What side effects can occur with the COVID-19 vaccine for kids under 5? Who should not receive the COVID-19 vaccine for kids under 5?
Should kids under 5 who’ve had COVID-19 still get vaccinated?
Should my child get the COVID-19 vaccine if they’re sick?
Will there be a vaccine for babies under 6 months?

What Are the Risks of COVID-19 for Kids Under 5?

Since the onset of the pandemic, millions of kids under 5 have had a positive COVID test and thousands have been hospitalized, Amin says. Of those children, the Centers for Disease Control and Prevention (CDC) notes 824 have died. According to Parikh says, rates of transmission for this age group have been high, especially since it’s hard to get young kids to wear masks, socially distance and practice good hygiene. Johns Hopkins Medicine also cautions kids under 2 years and those born prematurely may be at higher risk for more severe cases of COVID-19. Plus, a small subsect of children have developed other conditions after COVID, such as pneumonia, ear infections and multisystem inflammatory syndrome in children (MIS-C), Amin adds. MIS-C can lead to inflammation in various organs and body parts and typically requires treatment in a hospital, the CDC says. To date, there have been over 9,500 confirmed cases of MIS-C and 79 fatalities related to MIS-C.

Unfortunately, while some treatments have been approved to treat COVID in adults, that’s not the case for children, Amin says. There are currently no FDA-approved treatments for COVID for kids younger than 5 years old. For MIS-C, the AAP notes there’s currently no “known optimal treatment,” rather patient care and treatment approach should be case by case.

It’s important to know that, as of September 2023, cases in kids aged 0 to 4 are on the rise again, the American Academy of Pediatrics (AAP) says. While the age group only accounts for 25 percent of the US population, they’ve accounted for 50 percent of COVID-based hospitalizations since June 2023. The reason? Low vaccination rates, the org says—only 13 percent of kids aged 0 to 4 have been vaccinated, compared to 68 percent of kids aged 12 to 17.

What COVID-19 Vaccines Are Currently Available for Kids Under 5?

The initial bivalent vaccines approved for use in kids under 5 in June 2022 are no longer available. Instead, in October 2023, the US Food and Drug Administration (FDA) and CDC granted emergency use authorization for two updated Moderna and Pfizer-BioNTech vaccines for kids aged 6 months through 11 years that more effectively target current COVID-19 variants. While the vaccines are still only authorized for emergency use, the FDA maintains confidence in their safety, effectiveness and benefits based on extensive research.

Kids aged 6 months to 4 years who’ve had a previous vaccination can receive one or two doses of either updated vaccine, the FDA notes. Dosage will depend on age and each child’s COVID-19 vaccination history. Kids in this age group who’ve never been vaccinated should get three doses of the updated and authorized Pfizer-BioNTech COVID-19 vaccine or two doses of the updated authorized Moderna COVID-19 vaccine.

How Do the Updated COVID Vaccines for Kids Under 5 Work?

The updated vaccines utilize the same mRNA technology as the previous adult COVID-19 vaccine. The mRNA teaches our immune system how to make a “spike protein” that resembles the COVID virus, explains Preeti Parikh, MD, a New York City pediatrician and executive medical director at GoodRx, adding, “Your child’s body then makes antibodies against these spike proteins. If it encounters the COVID virus particles, the antibodies will attack the virus.” Children’s bodies destroy the mRNA in a couple of days but retain the knowledge of how to trigger an immune response, should they ever get exposed to COVID.

According to the CDC, like the vaccine for adults, the vaccines with EUA for kids under 5 do not contain a live virus. “It's the same exact technology science as the vaccines for older children and adults, it's just different dosing, depending on whether you get Moderna or Pfizer, compared to the adult population,” says Florida-based pediatrician Mona Amin, DO. The CDC also notes that kids will receive a smaller dose of the vaccine, compared to teenagers and adults.

How Effective is the COVID-19 Vaccine for Kids Under 5?

The FDA believes the updated COVID vaccines for babies, toddlers and preschoolers will be as effective as the vaccines for adults.

In their initial trials, leading to the June 2022 approval of the initial vaccines for kids under 5, the experts looked at the antibody immune response triggered by the vaccine. They found the response in kids under 5 who had completed their doses to be comparable to adults who had completed their doses. The initial Moderna vaccine was found to be 50.6 percent effective in preventing COVID in kids 6 to 23 months old and 36.8 percent effective in kids 2 through 5 years old. According to Pfizer, its initial vaccine was found to be 80.3 percent effective in kids 6 months to 4 years old. “Both vaccines can prevent mild symptoms…but most importantly it prevents serious illness and hospitalization,” Parikh says. “The effectiveness should be similar to the older kids.”

For its updated vaccines, the FDA reaffirms its stance that both have gone through rigorous oversight and are safe for use. While the updated vaccine targets current variants circulating, Amin warns that it’s hard to concretely measure effectiveness, as new variants will continue to pop up. “It's not that the vaccines aren’t great, it's just that the variants could outsmart the vaccine,” Amin says—but this doesn’t mean that kids under 5 shouldn’t be vaccinated. The vaccine still provides the best chance for reducing the risk of getting COVID and becoming severely ill, Amin says, but parents shouldn’t believe their child can’t ever catch COVID after being vaccinated.

Is the COVID-19 Vaccine Safe for Kids Under 5?

All major authorities on the subject believe the COVID vaccine to be safe for babies 6 months and up, toddlers and preschoolers. The FDA, CDC and AAP have all released statements based on the available data. All three organizations believe the vaccines are safe and will be effective at stopping the spread of COVID. “We don't know all of the information, but what we do know is that it's safe in trials and also in population data from children 5 and up that have been given the mRNA vaccine,” Amin adds.

What Side Effects Can Occur With the COVID-19 Vaccine for Kids Under 5?

According to AAP and CDC, the side effects for the updated COVID-19 vaccines are similar to previous formulations. The most commonly seen ones after administering the COVID vaccine in kids under 5 include:

Fever
Irritability or crying
Soreness, redness and swelling at the injection site
Sleepiness and fatigue
Loss of appetite
Swollen lymph nodes (usually in the underarm if administered in the arm, or in the groin if administered in the thigh)
Chills
Muscle aches or joint stiffness
Headaches
Nausea and vomiting

“These are symptoms that we see 48 hours after the vaccine, if they happen at all—not all children in the study have those side effects—and they went away on their own,” Amin adds.

The AAP does note that in the past there have been rare cases of anaphylaxis. There have also been extremely rare cases of myocarditis or pericarditis, which refer to the inflammation of the heart muscle and can be associated with symptoms of chest pain and irritability. However, the AAP notes these cases most often occurred in males aged 12 to 39. “I'm going to be honest, myocarditis is extremely rare in children under 5,” Amin says. “We don’t believe it's going to be something very significant in this age group.”

Another concern parents may have is febrile seizures, which typically occur in younger kids and are triggered by fever. However, the CDC maintains that febrile seizures were rare in past clinical trials for young kids. Plus, as Amin points out, 3 to 5 percent of young children get febrile seizures, regardless of whether or not they’ve received the COVID vaccine or have COVID, the flu or another illness that’s causing a fever. “It could be that the child was prone to febrile seizures…Children with COVID infection can get febrile seizures, children with the flu can get febrile seizures,” she says. “It’s definitely not something that’s super concerning, but it's something that parents should know.”

Who Should Not Receive the COVID-19 Vaccine for Kids Under 5?

According to the CDC, anyone who currently has COVID or MIS-C should wait to get the vaccine until they’ve recovered and it’s been about 90 days since the diagnosis. The CDC also advises to talk to your child’s doctor if they’ve had an allergic reaction to any previous vaccine, are allergic to any of the COVID vaccine ingredients or have an allergic reaction immediately after getting the COVID vaccine. “If you have an allergic reaction to the COVID vaccine, then you should not be getting future ones,” Amin says. Other than these factors, Amin and Parikh say there are no known reasons that would prevent anyone in this age group from getting the vaccine.

Should Kids Under 5 Who’ve Had COVID-19 Still Get Vaccinated?

Yes, experts recommend kids who’ve had COVID should still receive the vaccine, as it can help protect against future variants. While natural immunity is great, it’s not enough to protect against possibly aggressive new variants, Amin says. “This virus can outsmart us. The vaccine can add more protection than natural immunity.”

Should My Child Get the COVID-19 Vaccine If They’re Sick?

If your child is sick, first confirm it’s not COVID by getting them tested, Amin recommends. If the test is positive, the CDC recommends waiting three months (90 days) before getting your child vaccinated. Studies have shown that waiting three months after a positive test and then getting the vaccine can boost immunity, Parikh explains.

“If it's not COVID, as long as that child is fever-free for 24 hours and is back to normal spirits, they can get the vaccine,” Amin says.

Will There Be a Vaccine for Babies Under 6 Months?

According to Amin, babies under 6 months aren’t vaccinated against viruses like coronaviruses or the flu. This is due to a lack of studies looking at safety, as well as the possibility of some immunity carried over from a mom who’s been vaccinated or had the illness during pregnancy, she explains. “Most vaccine studies similar to the flu are done for 6 months and over, once [baby’s] immune system is a little more mature.”

Ultimately, getting your child vaccinated against COVID is a personal decision. Amin’s biggest advice to parents considering whether or not their children should get the COVID vaccine? Do your due diligence, talk to your pediatrician, make an honest effort to learn about the science behind the vaccine and weigh the benefits and risks to make an informed decision.

Plus, more from The Bump:

What to Know About COVID in Babies and Toddlers

FDA Approves COVID-19 Vaccines for Kids 6 Months and Up

What All Moms-to-Be Should Know About COVID in Pregnancy

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