COVID-19 vaccines for kids: What you need to know

Coronavirus disease 2019 (COVID-19) vaccines are available to children in the U.S. Here's what parents need to know about the safety and effectiveness of the vaccine, the possible side effects, and the benefits of getting vaccinated.

If children don't frequently experience severe illness with COVID-19, why do they need a COVID-19 vaccine?

While rare, some children can become seriously ill with COVID-19 after getting the virus that causes COVID-19.

A COVID-19 vaccine might prevent your child from getting the virus that causes COVID-19. It also may prevent your child from becoming seriously ill or having to stay in the hospital due to the COVID-19 virus.

What COVID-19 vaccines are available to kids in the U.S.?

In the U.S., COVID-19 vaccines are available to children based on their age. The number of shots, also called doses, depends on the vaccine and the child's vaccine history.

The COVID-19 vaccines available in the United States are:

  • Pfizer-BioNTech COVID-19 Vaccine 2024-2025 Formula. This vaccine is available for people age 6 months and older. This vaccine focuses on building protection against the KP.2 virus strain.

    Among people with a typical immune system:

    • Children ages 6 months up to age 4 years are up to date after three doses of the 2024-2025 Pfizer-BioNTech COVID-19 vaccine. If a child has had one dose of a previous Pfizer-BioNTech COVID vaccine, two doses of the 2024-2025 Pfizer-BioNTech COVID-19 vaccine will bring the child up to date. If a child had two doses previously, one dose of the 2024-2025 formula will bring the child up to date.
    • People age 5 and older are up to date with one 2024-2025 Pfizer-BioNTech COVID-19 vaccine.
  • Moderna COVID-19 Vaccine 2024-2025 Formula. This vaccine is available for people age 6 months and older. This vaccine focuses on building protection against the KP.2 virus strain.

    Among people with a typical immune system:

    • Children ages 6 months up to age 4 are up to date if they've had two doses of a 2024-2025 Moderna COVID-19 vaccine. If a child has had previous Moderna COVID vaccines, one dose of the 2024-2025 vaccine will bring the child up to date.
    • People age 5 and older are up to date with one 2024-2025 Moderna COVID-19 vaccine.
  • Novavax COVID-19 Vaccine, Adjuvanted 2024-2025 Formula. This vaccine is available for people age 12 years and older. This vaccine focuses on building protection against the JN.1 virus strain.

    Among people with a typical immune system:

    • People age 12 years and older are up to date if they've had one dose of a 2024-2025 Novavax COVID-19 vaccine.

In general, people age 5 and older with typical immune systems can get any vaccine that is approved or authorized for their age. They usually don't need to get the same vaccine each time.

Some people should get all their vaccine doses from the same vaccine maker, including:

  • Children ages 6 months to 4 years.
  • People age 5 years and older with weakened immune systems.
  • People age 12 and older who have had one shot of the Novavax vaccine should get the second Novavax shot in the two-dose series.

Talk to your healthcare professional if you have any questions about the vaccines for you or your child. Your healthcare team can help you if:

  • The vaccine you or your child got earlier isn't available.
  • You don't know which vaccine you or your child received.
  • You or your child started a vaccine series but couldn't finish it due to side effects.

How did the FDA determine the safety and effectiveness of the COVID-19 vaccines for use in kids?

For children ages 5 through 11, the FDA reviewed a vaccine study of more than 4,600 children in this age range. Of this group, about 3,100 were given the Pfizer-BioNTech COVID-19 vaccine. The other children were given an inactive (placebo) shot. Children who were given the vaccine were monitored for side effects for at least two months after the second dose. Side effects were generally mild to moderate.

The FDA also took an early look at cases of COVID-19 that occurred one week after children were given a second dose of the vaccine. None of the children in this analysis had been previously diagnosed with COVID-19. Among 1,305 children given the vaccine, there were three cases of COVID-19. Among 663 children given the placebo, there were 16 cases of COVID-19. The results suggest that the vaccine is about 91% effective in preventing COVID-19 in this age group.

For children ages 12 through 15, the FDA reviewed a vaccine study of more than 2,200 U.S. children in this age range. Of this group, about half were given the Pfizer-BioNTech COVID-19 vaccine. The other children were given a placebo shot. A week after the second dose was given, there were no cases of COVID-19 in the 1,005 children given the Pfizer-BioNTech vaccine.

Among 978 children given the placebo, there were 16 cases of COVID-19. None of the children had previously been diagnosed with COVID-19. The results suggest that the vaccine is 100% effective at preventing the COVID-19 virus in this age group. Also, a portion of the children in each age group were monitored for safety for at least two months after being given the second dose of the COVID-19 vaccine.

To find out the effectiveness of the Pfizer-BioNTech vaccine for children ages 6 months through 4 and the Moderna COVID-19 vaccine for children ages 6 months through 17 years old, the FDA looked at the immune responses of children in these age groups after they were fully vaccinated.

The FDA compared those responses to the immune responses of young adults who'd been given higher doses of the same mRNA vaccine.

As with the other vaccines, side effects were recorded. Some of the children were monitored for safety for at least two months after being fully vaccinated.

To find out how well the Novavax COVID-19 vaccine worked, the FDA reviewed data on 2,232 people ages 12 to 17. The research suggests that the vaccine was about 78% effective at preventing COVID-19 disease in this age group.

What are the side effects of the COVID-19 vaccines for kids?

Children given COVID-19 vaccines have side effects similar to those faced by adults. The most commonly reported side effects include:

  • Pain, redness or swelling where the shot was given.
  • Tiredness.
  • Headache.
  • Chills.
  • Muscle pain.
  • Joint pain.
  • Swollen lymph nodes.

Children ages 6 months through 3 years old also might cry, feel sleepy or lose their appetite after vaccination.

Similar to adults, children have side effects within two days after vaccination that typically last 1 to 3 days. More children reported these side effects, except for injection site pain, after the second dose of the vaccine. However, some people have no side effects.

It isn't recommended that you give your child a pain relief medicine before vaccination to prevent side effects. Ask your health care team about giving pain relief medicine that doesn't contain aspirin after your child gets a COVID-19 vaccine.

Can COVID-19 vaccines affect the heart?

In some people, COVID-19 vaccines can lead to heart complications called myocarditis and pericarditis. Myocarditis is the swelling, also called inflammation, of the heart muscle. Pericarditis is the swelling, also called inflammation, of the lining outside the heart.

The risk of myocarditis or pericarditis after a COVID-19 vaccine is rare. These conditions have been reported after a COVID-19 vaccination with any of the three available vaccines. Most cases have been reported in males ages 12 to 39.

If you or your child develops myocarditis or pericarditis after getting a COVID-19 vaccine, talk to a healthcare professional before getting another dose of the vaccine.

Of the cases reported, the problem happened more often after the second dose of the COVID-19 vaccine and typically within one week of COVID-19 vaccination. Most of the people who got care felt better after receiving medicine and resting.

Symptoms to watch for include:

  • Chest pain.
  • Shortness of breath.
  • Feelings of having a fast-beating, fluttering or pounding heart.

If you or your child has any of these symptoms within a week of getting a COVID-19 vaccine, seek medical care.

Are there any long-term side effects of the COVID-19 vaccines?

The vaccines that help protect against COVID-19 are safe and effective. The vaccines were tested in clinical trials. People continue to be watched for rare side effects, even after more than 650 million doses have been given in the United States.

Side effects that don't go away after a few days are thought of as long term. Vaccines rarely cause any long-term side effects.

If you're concerned about side effects, safety data on COVID-19 vaccines is reported to a national program called the Vaccine Adverse Event Reporting System in the U.S. This data is available to the public. The CDC also has created v-safe, a smartphone-based tool that allows users to report COVID-19 vaccine side effects.

If you have other questions or concerns about your symptoms, talk to your healthcare professional.

How do the mRNA COVID-19 vaccines work?

The Pfizer-BioNTech and the Moderna COVID-19 vaccines use messenger RNA, also called mRNA. Researchers have been studying mRNA vaccines for decades.

This type of vaccine gives your cells instructions for how to make the S protein found on the surface of the COVID-19 virus. After vaccination, your muscle cells begin making the S protein pieces and displaying them on cell surfaces. This causes your body to create antibodies. If you later become infected with the COVID-19 virus, these antibodies will fight the virus.

Once the protein pieces are made, the cells break down the instructions and get rid of them. The mRNA in the vaccine doesn't enter the nucleus of the cell, where DNA is kept.

Are there any children who shouldn't get a COVID-19 vaccine?

COVID-19 vaccines shouldn't be given to a child with a known history of a severe allergic reaction to any of the vaccine's ingredients. If this is the case, your child might be able to get different COVID-19 vaccine in the future.

Can a COVID-19 vaccine give a child COVID-19?

No. The COVID-19 vaccines currently available and being developed in the U.S. don't use the live virus that causes COVID-19.

Can children who get COVID-19 experience long-term effects?

Anyone who has had COVID-19 can develop a post-COVID-19 condition. Children and teens are less likely to have a post-COVID-19 condition. But long-term health issues can affect younger people. People with post-COVID-19 conditions report a wide range of symptoms.

When people younger than 18 who had COVID-19 were compared with those who didn't, researchers found higher rates of some health issues. Compared with those who never had COVID-19, young people who did have the disease were more likely to report:

  • Blood clot in the lung.
  • Blood clot in a vein.
  • Heart infection called myocarditis.
  • Thickening of the heart wall called cardiomyopathy.
  • Kidney failure.
  • Type 1 diabetes.

How can children get a COVID-19 vaccine?

Talk to your local health department, pharmacy or your child's health professional for information on where your child can get a COVID-19 vaccine.

How soon can a child get a COVID-19 vaccine before or after getting another vaccine?

A COVID-19 vaccine and other vaccines can be given at the same visit. COVID-19 vaccinations are now part of the immunization schedule for children age 6 months and older. Kids can get a COVID-19 vaccine during their well-child visit or anytime they become eligible based on the vaccination schedule.

If you have questions or concerns about your child getting a COVID-19 vaccine, talk to your child's health care team. The health professional can help you weigh the risks and benefits of vaccination.

Last Updated Sep 13, 2024


© 2024 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. Terms of Use