COVID Vaccines for Children Ages 5 to 11

The Pfizer-BioNTech COVID vaccine is now available for children ages 5 and over. At Stanford Children’s Health, we want to help our families make informed decisions. This handout will answer some of the most common questions about the COVID vaccine for children ages 5 to 11.

Which vaccine can children ages 5 to 11 get?

The Pfizer-BioNTech vaccine is approved for children ages 5 to 11 by the Centers for Disease Control (CDC) and the Food and Drug Administration (FDA).

This vaccine is given in 2 doses. 3 weeks after a child’s first shot, they can get their second shot. 2 weeks after their second shot, a child is considered fully vaccinated.

The Moderna and Johnson & Johnson/Janssen vaccines are still being studied for children ages 5 to 11 and are not approved yet.

How does the Pfizer vaccine work?

The Pfizer-BioNTech vaccine is an mRNA vaccine. This type of vaccine works by teaching the body to recognize the COVID virus. It does this by teaching the body to make proteins that look like one part of the virus. The body can then recognize the virus and fight it quickly in the future. Unlike other types of vaccines, mRNA vaccines do not contain any parts of the COVID virus.

Is the vaccine for children different than the vaccine for adults?

The vaccine is exactly the same for everyone, but children can get a smaller amount. Children ages 5 to 11 get a dose of 10 micrograms, while adults and children over age 12 get 30 micrograms. This is because young children have stronger immune systems and their bodies can become immune to viruses more easily.

What are the ingredients in the vaccine?

The Pfizer-BioNTech vaccine contains:

  • the mRNA, which teaches your body to make proteins that look like part of the COVID virus
  • fats called lipids, which help the mRNA get into your cells
  • salt and sugar, which keep the vaccine stable before it is given

There are no preservatives or allergens such as latex, eggs, or metals in the vaccine. There are no animal materials such as gelatin in the vaccine.

How do they know the vaccine is safe for children ages 5 to 11?

Pfizer had trials to make sure the vaccine is safe for children ages 5 to 11. In these trials, over 1500 children were given the COVID vaccine and 750 other children were given a placebo. A placebo is an injection with no vaccine in it, which helps scientists study the effects of the vaccine.

In these trials, the vaccine proved to be over 90% effective at preventing symptomatic COVID.

What are the side effects of the vaccine?

The side effects of the vaccine for children ages 5 to 11 are similar to side effects for adults and older children who get the vaccine. The most common side effects are:

  • pain where they got the injection
  • tiredness
  • headache
  • chills
  • fever
  • aches
  • rash

These side effects occur more after the second dose of the vaccine, and they usually go away in 1 to 2 days.

Why do young children need the vaccine if they don’t get very sick from COVID?

Since the rise in COVID variants such as the delta variant and the omicron variant, children are more likely to get the virus. Although COVID in children is usually milder than in adults, COVID still has many risks for children. Children can still be hospitalized and get very sick from COVID. Currently, COVID is in the top 10 most common causes of death for children under age 11.

The vaccine works very well to prevent severe illness and death from COVID in both children and adults.

The vaccine also helps reduce the spread of COVID. If your child is vaccinated, they are much less likely to pass the virus to others, including people who are at higher risk. Reducing the spread of COVID can also stop new variants, because the fewer people the virus can infect, the less the virus can change and become even more dangerous.

My child already had COVID. Should they still get vaccinated?

Yes, we recommend getting vaccinated even if someone already had COVID. It is possible to get COVID more than once. Studies show that people who are fully vaccinated are less likely to get COVID compared to people who already had COVID before.

My child is 11 years old but is about to turn 12. Which vaccine dose should they get?

If a child is 11 years old and will turn 12 before they receive their second dose of the COVID-19 vaccine, they will get the smaller dose of vaccine for their first dose, then the larger dose of vaccine for the second dose.

Talk with your care team if you want your child to receive either 2 smaller doses or 2 larger doses instead. We will do our best to give your child the vaccine doses you prefer, depending on their weight and medical history.

Is the COVID vaccine bad for my child’s heart?

There have been no reported cases of myocarditis, or heart muscle inflammation, in children ages 5 to 11 after getting vaccinated. Myocarditis has been reported as an extremely rare side effect after the second dose of the vaccine in males ages 16 to 29. However, the risk of myocarditis is much higher after getting COVID than it is after getting the COVID vaccine.

Does the vaccine affect fertility?

There is no evidence than COVID vaccines affect or reduce fertility at all.

Does the vaccine alter or change a person’s DNA?

No, COVID vaccines do not alter or change a person’s DNA at all. It is not possible for the vaccine to enter your cells in a way that could affect your DNA.

How can I get a COVID vaccine for my child?

You can make a vaccination appointment at Stanford Children’s Health by visiting or calling (844) 365-0724 (option 3). You can also make an appointment through MyChart by selecting “Manage your appointments.”

Where can I learn more?

If you have any questions or concerns about giving the COVID vaccine to your child, ask your child’s pediatrician or a member of their care team.

You can also visit to learn more about vaccines at Stanford Children’s Health or to learn more about the CDC recommendations.