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The Science Behind COVID-19 Vaccines: Parent FAQs

The Science Behind the COVID-19 Vaccine: Parent FAQs The Science Behind the COVID-19 Vaccine: Parent FAQs

​Since COVID-19 vaccines became available to anyone age 12 and up in May 2021, millions of adolescents have been safely vaccinated. Now, children 5 to 11 years old can get vaccinated, too.

Whether you're the parent of a teen or a grade-school age child, you likely have questions about the vaccine. And top-of-mind for many parents is how we know that it is safe for kids.

Here are answers to some common questions about the science behind the COVID-19 vaccine.

How does the COVID-19 vaccine work?

The COVID-19 vaccine works similarly to other vaccines your child has had. Germs such as SARS-CoV-2, the virus that causes COVID-19, invade and multiply inside the body. The vaccine helps stop this by teaching the immune system to recognize and make antibodies that fight the virus.

After your child is fully vaccinated, there is less of a chance they will get COVID-19. And if they do get infected with the virus, including the widely circulating Delta variant, they likely will not be as sick as they would without the vaccine. They also are much less likely to be hospitalized if they get the virus.

How are mRNA and viral vector COVID-19 vaccines different?

There are two types of vaccines currently available in the United States: messenger ribonucleic acid (mRNA) vaccines (Pfizer & Moderna) and a "viral vector" vaccine (Johnson & Johnson). They all have the same result — protecting people from COVID-19. Their delivery systems are just a bit different.

Right now, children and adolescents 5 to under 18 in the U.S. can only receive the COVID-19 mRNA vaccine from Pfizer BioNTech. People 18 years and up can get either COVID-19 mRNA vaccine (Moderna or Pfizer BioNTech) or the viral vector vaccine (Johnson & Johnson).

  • COVID-19 mRNA vaccines contain messenger RNA (mRNA), mRNA is made up of nucleic acids, which are the building blocks of all our cells. The mRNA carries instructions inside a lipid (fat) coating that tells cells to produce harmless pieces of "spike" protein. These look like spikes on the actual COVID virus.

    When the cells make these pieces of spike protein, the immune system recognizes that they should not be there. Your child's body then makes antibodies that get rid of the spike pieces. These antibodies remember how to protect your child from the virus in the future.

Did you know?

Even though widespread use of mRNA vaccines is new, this technology has been studied for decades. mRNA vaccines do not contain any live or dead parts of the virus.

  • Viral vector vaccines also give instructions to your immune cells. The instructions are carried in a harmless virus that has been changed so it is not able to copy itself, spread and make your child sick.

    The process is similar to the way the mRNA vaccine works. Cells create the protein that is found on the virus that causes COVID-19. The person's immune system makes antibodies to get rid of the virus, and that can remember how to protect them from getting very sick from the virus in the future.

Do mRNA vaccines change your DNA?
No, the COVID-19 vaccines made with messenger RNA do not interact with your DNA at all. DNA is your genetic material and it is stored in the nucleus of a cell. The mRNA in the vaccines never gets into the nucleus. And once your immune cells have used the instructions, they break down the mRNA and it quickly exits the body.

What about boosters?

  • The mRNA vaccines are given in a two-dose series. Some adults can get a single booster dose at least 6 months after they completed the initial vaccine dose series.

  • The viral vector vaccine available in the United States is given in one dose. A booster dose is recommended at least two months after completion of the first dose. People 18 years and older can get a second dose of the viral vector vaccine or get one of the mRNA vaccine booster doses instead if they prefer.

Can children with immune conditions get a third dose?

A third dose is available for certain adolescents (age 12 and up) and adults who have medical conditions or take medicines that weaken the immune system.

How do we know COVID-19 vaccines are safe for kids?

Tens of thousands of volunteers were involved in clinical trials for the vaccines. The clinical trials showed that the COVID-19 vaccines are remarkably safe and effective before they got FDA emergency use authorization. Clinical trials are now underway to study whether children as young as six months old could receive COVID-19 mRNA vaccines.

Nearly half of all kids 12- to 17 years old in the U.S. have been fully vaccinated! That's more than 11 million kids who have had both of their doses of COVID-19 vaccine. The vaccines continue to be monitored very closely. In fact, the Centers for Disease Control and Prevention (CDC) say that COVID-19 vaccines will have "the most intensive safety monitoring in U.S. history."

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American Academy of Pediatrics (Copyright © 2021)
The information contained on this Web site should not be used as a substitute for the medical care and advice of your pediatrician. There may be variations in treatment that your pediatrician may recommend based on individual facts and circumstances.
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