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Kids and the COVID-19 vaccine

Children 6 months and older are eligible to receive the COVID-19 vaccine, which is one of the best ways to protect kids from severe cases of the virus. For answers to some frequently asked questions, read more below.

Children ages 6 months + are now eligible to receive the Pfizer and Moderna COVID-19 vaccine. Search for a COVID vaccine appointment in Connecticut or the U.S.

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COVID Vaccine for Kids 6 Months to 5 Years

Why should I vaccinate my child under 5?

Every family will need to make a decision that is right for them. However, there are several things worth considering.

With the rise of COVID-19 variants, we are seeing more kids getting admitted to Yale New Haven Children’s Hospital for COVID-19, as well as other respiratory illnesses that are currently circulating. While some of these children have underlying health conditions, others do not. It is hard to predict which child will get a severe case of COVID-19. Getting vaccinated is the best way to protect against severe illness and hospitalization.

In addition, these vaccines have a remarkable safety profile. Millions of people have safely gotten vaccinated and during the pediatric vaccine trials, no serious adverse outcomes were reported. The safety profile of the COVID-19 vaccines is on par with other common childhood vaccinations.

What vaccine will kids receive?

There are two vaccines for kids. The Moderna vaccine is a 2-dose primary series for kids 6 months to 4-years-old. The Pfizer vaccine is a 3-dose series for kids 6 months to 4-years-old.

Kids ages 6 months–4 years who completed a Moderna primary series can now receive 1 bivalent Moderna booster dose at least 2 months after completion of the primary series.

The previously authorized 3-dose Pfizer-BioNTech primary series for children ages 6 months–4 years has been revised as follows: a monovalent Pfizer-BioNTech vaccine is administered for the first and second doses, followed by 1 bivalent Pfizer-BioNTech vaccine as the third primary series dose, at least 8 weeks after the second monovalent primary series dose.

A booster dose is not authorized for children in this age group who receive a Pfizer-BioNTech 3-dose primary series, including children who previously received a 3-dose monovalent Pfizer-BioNTech primary series.

How large is the dose for kids under 5?

The dose available for kids under 5 is a smaller dose compared to what is given to adults. For example, the adult dose for the Pfizer vaccine is 30 micrograms, while the dose for this age range in kids is 3 micrograms. The adult dose for the Moderna vaccine is 100 micrograms, compared to 25 micrograms for kids 6 months to 5-years-old.

Do kids under 5 need all the recommended doses?

Yes. During the vaccine trials, researchers found 2-doses of the Pfizer vaccine was not sufficient, which is why the recommendation is now for 3-doses. To ensure your child is getting the best protection against COVID-19, they should receive all of the recommended doses.

What are the side effects in kids under 5?

Common side effects include tiredness, headaches, pain where the shot was given, and chills. Less common but other known side effects are fever, diarrhea, joint aches, vomiting and swollen lymph nodes in the same area as the shot. These reactions show that your child’s body is making a good response to the vaccine and most should go away within 1-2 days, except swollen lymph nodes may last up to about 10 days.

What should my child do if they have side effects?

There are a few ways to address vaccine side effects:

  • Use an ice pack or cool, damp cloth to help reduce redness, soreness and/or swelling at the place where you child’s shot was given.
  • A cool bath can also be soothing.
  • Have your child drink liquids often for 1-2 days after getting the vaccine.
  • Over-the-counter pain relievers (such as ibuprofen or acetaminophen) may be given if your child develops side effects after the vaccine, unless your child has been advised not to take over-the-counter pain relievers. You may follow the dose directions on the box or speak to your child’s pediatrician.
    • Do not give aspirin to children under the age of 18 years.

When should I seek medical care for my child after a vaccine?

Although very unlikely, if your child experiences emergency warning symptoms at any time after receiving their COVID-19 vaccine, call 911 immediately. Emergency warning symptoms include trouble breathing, pain or pressure in the chest that doesn’t go away, new confusion or difficulty waking up, bluish lips or face, or any other sudden and severe symptom.

For symptoms that are severe or last 72 hours or more, contact your child’s pediatrician.

When should I get my child tested for COVID-19?

The following symptoms suggest COVID-19 infection and are not common vaccine side effects:

  • New loss of smell or taste
  • Cough or shortness of breath
  • Stuffy nose/sore throat/runny nose/pink eye
  • Nausea/vomiting or diarrhea

If your child has one or more of these symptoms, contact your child’s pediatrician to arrange a COVID-19 test.

If your child does have a positive COVID-19 test between their first and second doses of COVID-19 vaccine, they should wait 10 days from when they first tested positive and be fully back to normal before getting their second dose. They should still get the second dose.

Can my baby or toddler get the COVID-19 vaccine along with other vaccinations?

Yes. It is perfectly safe to get this vaccine along with other vaccines.

My child recently had COVID-19, how long do I have to wait to vaccinate them?

Kids can get vaccinated once they have completed their isolation period and symptoms have resolved. Yale New Haven Health recommends an isolation period of 7 days. Those who were hospitalized due to COVID-19 may need to wait longer before getting vaccinated and parents should check with their pediatrician before booking an appointment.

COVID-19 Vaccine Safety for Kids

What is myocarditis?

Myocarditis is an inflammation of the muscle cells. It is an extremely rare condition seen in well below 1% of vaccinated teenagers. We have seen a handful of cases, mostly in young male adults after receiving their COVID-19 vaccine. Symptoms typically occur within two weeks of vaccination and can include chest pain, or difficulty breathing. If you experience those symptoms, seek medical attention.

It is important to note that myocarditis can be treated with anti-inflammatory drugs and our pediatric cardiologists are well trained to deal with any cases. The patients we have seen with myocarditis have had a good recovery. In addition, vaccination is still recommended, as the complications from COVID-19 may be much worse than myocarditis in some children.

Can my child get the vaccine if they have food allergies, a history of anaphylaxis, and/or carries an Epi-pen?

Unless your child had an allergic reaction to a previous dose of the COVID-19 vaccine or has an allergy to one of the ingredients in the vaccine (e.g., polyethylene glycol or PEG), your child should be able to get the vaccine. If you have concerns regarding your child’s history of allergic reactions, you should discuss your child’s history with your pediatrician before getting the vaccine.

If your child has a history of a severe allergic reaction or carries an Epi-pen, please let our staff know on the day of your child’s appointment. They will be able to monitor your child and respond in case they experience a reaction.

My child had a reaction to Miralax or another medication that contains PEG (polyethylene glycol). Is it safe for my child to get the Pfizer vaccine?

If your child has had a severe allergic reaction (e.g., anaphylaxis), or an immediate allergic reaction of any severity to Miralax or another medication that contains polyethylene glycol (PEG), your child cannot receive the Pfizer COVID-19 vaccine. Symptoms of this type of allergic reaction include diffuse itching, hives, swelling of face/lips, respiratory distress (e.g. wheezing, stridor) with onset within minutes to hours of taking the medication.

A common, known (intended) effect of orally administered polyethylene glycol is abdominal discomfort and diarrhea. This type of reaction would NOT be considered an allergic reaction unless accompanied by allergic symptoms such as itching, rash, facial swelling, or difficulty breathing.

My child has a history of multisystem inflammatory syndrome (MIS-C). Can my child receive a COVID-19 vaccine?

Children and young adults who had MIS-C may choose to be vaccinated. If they decide to get the vaccine, CDC suggests they should consider delaying COVID-19 vaccination until they have recovered from this illness and for 90 days after the date of diagnosis of MIS-C.

I have heard that the COVID-19 vaccines may impact fertility. Is there any evidence for this?

There is no evidence that mRNA vaccines for COVID-19 have a negative effect on fertility and theories about COVID-19 vaccines impacting fertility have no scientific basis. Claims that mRNA vaccines will cause the immune system to attack genes or proteins important for reproduction are unfounded and have been refuted by reproductive scientists across the world. The American College of Obstetricians and Gynecologists, the American Society for Reproductive Medicine, and the Society for Maternal-Fetal Medicine continue to assert that COVID-19 vaccines do not affect fertility.

I have heard that some women have experienced menstrual irregularities after a COVID-19 vaccine. Should I be worried about this in my daughter?

At this time, there is no scientific evidence that COVID-19 vaccines themselves cause menstrual changes. Period timing and flow volume can vary due to numerous causes, including stress, illness, and age. Individual patient reports of heavier periods being a temporary side effect of the vaccine could thus be attributable to many other causes. Menstrual irregularities should not be a cause for concern about the vaccine.

pediatric minute

Pediatric Minute

Dr. Thomas Murray discusses the introduction of the COVID-19 vaccine for children under 5 years old.

Watch the video