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

September 11, 2021
Article

Learn about the safety and effectiveness of COVID-19 vaccines for kids, the possible side effects, and the benefits of vaccination.

A coronavirus disease 2019 (COVID-19) vaccine is now available to children ages 12 through 15 in the U.S. Here's what parents and kids need to know about the safety and effectiveness of the vaccine, the possible side effects, and the benefits of getting vaccinated.

What COVID-19 vaccine has been approved for kids?

The U.S. Food and Drug Administration (FDA) has given the Pfizer-BioNTech COVID-19 vaccine emergency use authorization for children ages 12 through 15. The FDA has also approved this vaccine, now called Comirnaty, to prevent COVID-19 in people age 16 and older.

The Pfizer-BioNTech COVID-19 vaccine requires two injections given 21 days apart. The second dose can be given up to six weeks after the first dose, if needed.

Research has shown that the Pfizer-BioNTech COVID-19 vaccine is 100% effective in preventing COVID-19 in children ages 12 through 15. The vaccine is 91% effective in preventing severe illness with COVID-19 in people age 16 and older. Early research also suggests that the vaccine is 96% effective at preventing severe disease with COVID-19 caused by the delta variant, the most common COVID-19 variant in the U.S right now.

How did the FDA determine the safety and effectiveness of the Pfizer-BioNTech COVID-19 vaccine for use in kids ages 12 through 15?

The FDA reviewed a study of more than 2,200 U.S. children ages 12 through 15. Of this group, about half were given the Pfizer-BioNTech COVID-19 vaccine. The other children were given an inactive (placebo) shot.

A week after the second dose was given, research showed 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 COVID-19 in this age group.

What are the side effects of the Pfizer-BioNTech COVID-19 vaccine for kids ages 12 through 15?

Children ages 12 through 15 given the Pfizer-BioNTech COVID-19 vaccine had side effects similar to those experienced by people age 16 and older. The most commonly reported side effects include:

  • Pain where the shot was given
  • Fatigue
  • Headache
  • Chills
  • Muscle pain
  • Fever
  • Joint pain

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

After your child is given a COVID-19 vaccine, he or she will be monitored for 15 to 30 minutes to see if he or she has an allergic reaction that requires treatment.

It isn't recommended that you give your child an over-the-counter pain reliever before vaccination to prevent side effects. It's OK to give this kind of medication after your child gets a COVID-19 vaccine.

Can COVID-19 vaccines affect the heart?

In the U.S., there has been an increase in reported cases of myocarditis and pericarditis after mRNA COVID-19 vaccination, particularly in male adolescents and young adults age 16 and older. Myocarditis is the inflammation of the heart muscle, while pericarditis is the inflammation of the lining outside the heart. These reports are rare. The Centers for Disease Control and Prevention (CDC) is investigating to see if there is any relationship to COVID-19 vaccination.

Of the cases reported, the problem happened more often after the second dose of the COVID-19 vaccine and typically within several days after COVID-19 vaccination. Most of the people who received care quickly 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.

Is there any research on the long-term effects of the Pfizer-BioNTech COVID-19 vaccine?

Because COVID-19 vaccine clinical trials only started in the summer of 2020, it's not yet clear if the vaccines will have long-term effects. However, vaccines rarely cause long-term effects.

A portion of the children ages 12 through 15 enrolled in the ongoing Pfizer-BioNTech COVID-19 vaccine study were monitored for safety for at least two months after being given the second dose of the COVID-19 vaccine.

As part of its first request for emergency use authorization of its COVID-19 vaccine in 2020, Pfizer Inc. created a safety monitoring plan. The plan now includes the monitoring of adolescents given the COVID-19 vaccine.

In addition, in the U.S. all vaccination providers are required to report serious adverse events, such as allergic reactions, to a national program called the Vaccine Adverse Event Reporting System.

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

A COVID-19 vaccine can prevent your child from getting and spreading the virus that causes COVID-19. If your child gets COVID-19, a COVID-19 vaccine could prevent him or her from becoming severely ill.

Getting a COVID-19 vaccine will also allow your child to start doing things that he or she might not have been able to do because of the pandemic.

How does the Pfizer-BioNTech COVID-19 vaccine work?

The Pfizer-BioNTech COVID-19 vaccine uses messenger RNA (mRNA). Researchers have been studying mRNA vaccines for decades.

Coronaviruses have a spikelike structure on their surface called an S protein. COVID-19 mRNA vaccines give instructions to immune cells for how to make a harmless piece of an S protein. After vaccination, cells begin making the protein pieces and displaying them on cell surfaces. The immune system recognizes the protein and begins building an immune response and making antibodies. 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.

Is there any difference in the ingredients or dosing of the Pfizer-BioNTech vaccine for people age 16 and older and for children ages 12 through 15?

No. The ingredients and dosing of this vaccine are the same for all age groups.

Are there any children who shouldn't get the Pfizer-BioNTech COVID-19 vaccine?

This vaccine is not yet available to children younger than age 12. Clinical trials involving younger children are in progress.

The vaccine also shouldn’t be given to a child with a known history of a severe allergic reaction to any of its ingredients. If this is the case, your child might be able to get another COVID-19 vaccine in the future.

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

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

Can a COVID-19 vaccine affect fertility or menstruation?

There is no evidence that any COVID-19 vaccines cause fertility problems.

A small number of women have reported experiencing temporary menstrual changes after getting a COVID-19 vaccine. A small study has also shown that some women experienced temporary menstrual changes after getting COVID-19. It’s not clear if getting COVID-19 or a COVID-19 vaccine causes these changes. Further research is needed.

Keep in mind that many things can affect menstrual cycles, including infections, stress, sleep problems and changes in diet or exercise.

How can children ages 12 through 15 get a COVID-19 vaccine?

Consult your local health department, pharmacy or your child’s doctor for information on where your child can get a COVID-19 vaccine. When making an appointment for your child to get a COVID-19 vaccine, consider asking these questions:

  • Does a parent or guardian need to be present at the appointment?
  • What information will need to be provided during the appointment?
  • Is there a limit on how many family members, such as siblings, can attend the appointment?

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 on the same day.

Previously, due to the newness of COVID-19 vaccines, the CDC had recommended against getting any other vaccines two weeks before and after getting a COVID-19 vaccine. The CDC changed its recommendation based on safety data gathered in recent months.

What can my child do after getting a COVID-19 vaccine?

After being fully vaccinated, your child can more safely return to doing the things that he or she might not have been able to do because of the pandemic.

Your child is considered fully vaccinated two weeks after the second dose of the Pfizer-BioNTech COVID-19 vaccine.

In the U.S., your child also won't need to quarantine or get a COVID-19 test after a known exposure if he or she doesn't have symptoms, with some exceptions for specific settings.

Remember, COVID-19 vaccination will protect most people from getting sick with COVID-19. If you have questions or concerns about your child getting a COVID-19 vaccine, talk to your child's doctor. He or she might be able to help you weigh the risks and benefits.