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Answering your questions about the COVID-19 vaccine for kids

Updated November 4, 2021. For the most updated COVID-19 information, please visit childrensmercy.org/coronavirus

We just received authorization for children ages 5-11 years old to get the COVID-19 vaccine. We know you probably have questions about your child getting the vaccine. We’ve provided answers to some of the questions we’ve most frequently been asked. Getting kids vaccinated helps protect everyone. The more people vaccinated, the less transmission of COVID-19 in our community. You can find additional resources about the COVID-19 vaccine on the Children’s Mercy website at cmkc.link/vaccineFAQ.

Has the vaccine been properly tested?

It is normal to have questions about any new medical treatment or vaccines. The COVID-19 vaccines have gone through the same thorough evaluation, clinical trials and independent reviews as every other vaccine or medication. They were able to go through this cycle and be produced and tested more quickly because the U.S. government, many drug and biotech companies and academic institutions all worked together to develop safe and effective vaccines. The trials to test the vaccine were able to enroll children more quickly than other vaccine trials because many parents and children wanted to participate. Although the process was faster because of these reasons, the vaccines went through the same safety and efficacy evaluation as other vaccines and medications.

Additionally, the vaccine uses messenger RNA (mRNA), a technology which has been around for more than 10 years and has already been used as a cancer treatment. This is not a new type of technology, which is one of the reasons that pharmaceutical companies were able to develop the vaccines quickly.

Is there a chance of long-term side effects from the vaccine that we just don’t know yet?  

Based on all we know about the safety of these available vaccines, and all we know about how vaccines in general work to train your own immune system to fight infection, no long-term side effects of the vaccine are expected. The mRNA used in the COVID-19 vaccines only stays in the body for a short period of time before it is broken down.

Are kids getting sick from COVID-19? If they are more likely to get mild symptoms, why do they need the vaccine?

Kids are getting sick due to COVID-19. Unfortunately, during the delta variant surge, more kids than ever were getting sick from the virus. Although kids are less likely to get really sick or die from COVID-19, many children have required hospitalization and in those who get hospitalized, many end up needing care in the intensive care units and require machines to help them breathe. More kids have died from COVID-19, than the number of kids that die each year from the flu. Also, even kids that get only mild symptoms or no symptoms at all, can still spread the infection to others.

What side effects can we expect?

When the vaccines were tested, the most common side effect was pain at the injection site, and it was generally mild. Other common reactions were fatigue, headaches, muscle pain and chills. Fever was an uncommon side effect. These post-vaccination symptoms are a sign that the body is reacting properly to the vaccine. Essentially, it shows you that your immune system is revving up to protect you. The common side effects seen in children are similar to those seen in adults.

Should we be concerned about reports of myocarditis? 

Myocarditis is inflammation of the heart muscle, and pericarditis is inflammation of the outer lining of the heart. In both cases, the body’s immune system causes inflammation in response to an infection or some other trigger. Cases of myocarditis have rarely been reported after mRNA COVID-19 vaccination. Most commonly this occurs in male adolescents and young adults, more often after the second vaccine dose, and usually within the first week after vaccination.

Most patients with myocarditis or pericarditis who received care responded well to medicine and rest and felt better quickly. Patients can usually return to their normal daily activities after their symptoms improve and long-term side effects have not been seen. Myocarditis is much more frequently caused by COVID-19 infection as compared to the vaccine and the benefits of preventing COVID-19 infection in children far outweighs the risk of myocarditis caused by vaccine. Close monitoring will continue to evaluate cases of adverse effects of the COVID-19 vaccines, including myocarditis.

If our family has already had COVID-19, do my kids still need the vaccine?

Yes, everyone who is eligible should still get the vaccine, even if they have already had COVID-19. We know that people can get infected with COVID-19 more than once. In one study, people who had previously had COVID-19 but had not been vaccinated were twice as likely to get COVID-19 again than those who had previously had COVID-19 and been vaccinated.

If I have an 11-year-old, should I wait until they turn 12 to get the higher dose?

No. As soon as a child is eligible for the vaccine, they should get it. There is no reason to wait for a child to be 12 to get the vaccine, once the vaccine is authorized for those 5-11 years of age.

When will vaccines for little ones be authorized?

After the 5–11-year-olds are authorized to receive the vaccine, the next group will likely be 2-4-year-olds. Because younger children often receive different vaccine doses and have a different immune system compared with older children and adults, the vaccines are undergoing thorough safety evaluations in the younger age groups as well. Typically, vaccine trials start in older children and then go down to younger children once we know the vaccine is safe.

Can kids get the flu and COVID-19 vaccines at the same time?

Yes, a child can get COVID-19 with any other recommended vaccine, including the flu vaccine. It is a great idea to get caught up on all vaccines and the COVID-19 vaccine can be administered with other vaccines.

How do I talk to my friends who are nervous about getting the vaccine for their kids?

Talking to people who have already received the COVID-19 vaccine can be helpful to walk friends through what to expect. You can find additional information and resources at childrensmercy.org/covid-vaccine. The Centers for Disease Control and Prevention also has really helpful information on providing answers to common myths about the vaccine. And the American Academy of Pediatrics has a really helpful parents FAQ website that provides clear facts about the vaccines.  

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Pediatric Infectious Diseases, Clinical Pharmacology

Professor of Pediatrics, University of Missouri-Kansas City School of Medicine; Research Assistant Professor of Pediatrics, University of Kansas School of Medicine

Pediatric Infectious Diseases

Program Director, Infectious Diseases Fellowship; Professor of Pediatrics, University of Missouri-Kansas City School of Medicine; Education Assistant Professor of Pediatrics, University of Kansas School of Medicine