UF Health expert Q&A on vaccine for kids 5-11

On Tuesday the Centers for Disease Control and Prevention authorized use of the Pfizer-BioNtech vaccine, now known as Comirnaty, in children who are 5 to 11 years old. The decision followed Food and Drug Administration approval last week and coincides with Biden administration efforts to distribute the vaccine to as many as 28 million children in the coming months. 

Dr. Sonja A. Rasmussen, a professor in the departments of pediatrics and epidemiology at the UF College of Medicine and the UF College of Public Health and Health Professions, took time to answer questions parents may have about the vaccine.

Question: How does this vaccine work?

Answer: This is an mRNA vaccine. That means that the vaccine contains instructions (mRNA) that teach our cells to make a piece of a protein that is part of the virus that causes COVID-19. Our bodies then react by building up immunity to that protein. Then, in the future, if your child is exposed to COVID-19, their bodies will already know how to fight it off. These vaccines have been shown to reduce the chances of becoming infected and getting severely ill from COVID-19.

The vaccine does not contain the COVID-19 virus. That means that the vaccine cannot give your child COVID-19.

As with adults, this vaccine requires two doses given three weeks apart. The COVID-19 vaccine can be given at the same time as other vaccines, such as the flu vaccine.

Q: Why should kids this age (5-11) get vaccinated?

A: The most important reason for getting the vaccine is to reduce the risk of severe illness or death. The vaccine also reduces the risk of long COVID—a condition in which people can have the effects of COVID for months after the initial infection. Getting the vaccine also reduces the risk of passing the virus on to others who might be particularly vulnerable to COVID-19, such as grandparents or people with underlying conditions.

Q: Aren’t serious COVID-19 cases rare in this age group?

A: Kids are at a lower risk of severe disease from COVID-19, but that doesn’t mean that they’re at no risk. More than 700 children, including nearly 100 children ages 5-11 years, have died in the United States since the COVID-19 pandemic began, and tens of thousands of children have needed to go to the hospital.

Kids with underlying conditions such as obesity, diabetes and asthma are at the highest risk for severe disease, but about one-quarter of COVID-19 deaths among children were in previously healthy children. 

Q: What is the difference between emergency use authorization of a vaccine and the normal approval process? Is there any legitimate medical reason to wait to have my child vaccinated?

A: Emergency use authorization, or EUA, is a way for the FDA to make vaccines and medications available during a public health emergency such as the COVID-19 pandemic. For these vaccines to be made available through an EUA, companies were required to submit studies on tens of thousands of participants. These studies included all three phases of clinical trials that are typically used to approve vaccines and medications for use.

That means that vaccines that have received authorization through the EUA process have been rigorously tested and are shown to be safe and effective. To receive full approval by the FDA, data on the whole vaccine manufacturing process and facilities as well as additional safety data are reviewed by the FDA.

In August, the Pfizer/BioNTech COVID-19 vaccine received full FDA approval for persons 16 years and older.

Q: Compared with adults and teenagers, how well does the COVID-19 vaccine work in children ages 5-11?

A: The dose of the vaccine for children ages 5-11 years is one-third of what is used in adolescents and adults. This dose was shown to result in a strong immune response, based on the measurement of antibodies one month after the second dose of vaccine. The results were similar to those seen in people 16-25 years of age who received the higher adult dose of the vaccine. The vaccine was shown to be more than 90 percent effective against symptomatic COVID-19.

Q: What have been the most common side effects in kids ages 5-11 during clinical trials and how prevalent are they?

A: The side effects were similar to those seen in adults. These include a sore arm, fatigue, muscle aches, headache or fever. These side effects usually go away in a day or two. These are signs that the immune system is responding to the vaccine—so it is ready to tackle COVID-19 in the future.

Q: If my child takes medicine for post-vaccine side effects, will that diminish the level of immunity that develops?

A: We don’t know for sure if taking Tylenol or another medicine reduces the immunity from COVID-19 vaccines. Studies of other vaccines suggest that might be the case. For that reason, it is not recommended that you give your child a pain reliever before getting their COVID-19 vaccine to prevent side effects. Talk to your doctor about what medications your child can take for pain or discomfort after getting the COVID-19 vaccine.

Q: Among children ages 5-11, who should not get the vaccine?

A: Millions of people in the United States have safely received the COVID-19 vaccine. The only people who should not get the COVID-19 vaccine are people who have had a severe reaction (such as trouble breathing) or an immediate allergic reaction to any ingredient contained in the COVID-19 vaccine. Children who have had severe allergic reactions to eggs or any other vaccine can get the COVID-19 vaccine. However, they should be observed for 30 minutes after getting the vaccine, instead of the 15 minutes required for others. 

Q: What can you explain about dosing? If my child is above or below the weight norms for their age, will that affect the vaccine’s effectiveness?

A: The dose recommended for children 5-11 years of age is a third of that used for adolescents and adults (10 micrograms for 5-11 year olds compared with 30 micrograms for adolescents and adults).

Children are not just small adults. Their immune systems respond differently. Different doses were tested in children ages 5-11 and the 10-microgram dose was found to be safe while also giving an effective immune response. Children ages 5-11 who got the lower dose of the vaccine had a similar immune response to persons ages 16-25 years who received a higher dose.

There is no need to ask for a different dose based on your child’s weight. For some medications (such as Tylenol), a dose for children is calculated based on their weight, but that is not necessary for this or other vaccines. That is because medications work by entering the bloodstream, while a vaccine works by making an immune response at or near the injection site.

Q: Where and when will kids be able to get vaccinated?

A: A few days after the vaccine is authorized by the FDA and recommended by Centers for Disease Control and Prevention (CDC), it is expected to be widely available in pediatricians’ offices, pharmacies and some schools. These groups are looking forward to being able to protect kids 5-11 years of age from COVID-19 and will be ready when the vaccine for them becomes available.