All Your Questions About the COVID Vaccine for Kids Under 5, Answered

Why is authorization taking so long? We explain.

A young girl wearing a mask holds her mother's hand.

Last week, the Food and Drug Administration (FDA) postponed its decision on whether to extend Emergency Use Authorization of the Pfizer COVID vaccine to kids under 5, thrusting many parents with toddlers and preschoolers back into limbo. Patience is wearing thin for many parents of children in this age group — some of whom don’t know a world before the COVID-19 pandemic and today represent one of the largest unvaccinated groups in the U.S.

Sure, children, and especially young children, tend to have milder COVID infections than adults when they contract the virus. However, the highly transmissible Omicron variant has infected more than 1.9 million kids, and between 0.1 percent and 1.5 percent of reported cases are severe enough to require hospitalization, according to the American Academy of Pediatrics. Long-term impacts of COVID on affected kids are expected to me mild, but widely unknown. It’s an experiment many parents would like to avoid — with the help of a vaccine that has been proven wildly effective at keeping adults and older kids out of the hospital.

So where’s this vaccine? To understand what’s going on with the COVID vaccine for kids under 5, the threats of new variants to this age group, and how parents should be making decisions as they trudge through the next few months of the pandemic, Fatherly spoke to Tina Tan, M.D., a pediatric infectious disease specialist at the ​​Northwestern University Feinberg School of Medicine.

First of all, from where you stand, what are the risks of contracting COVID for children under 5?

I think one of the problems is that people have always thought kids under 5 or kids in general don’t get COVID-19 as rapidly as older individuals. And that is so untrue. Omicron is much, much more transmissible than any of the other variants and really has had a significant impact on the children that have been infected with that particular variant. Kids under 5 are definitely at risk, and because of the transmission of the variant, they’re actually at a fairly high risk of getting COVID-19 from someone else.

We know in the last four weeks, there have been three million children infected with COVID. Overall, since the start of the pandemic, there have been about 12.5 million kids [infected with COVID], so you can see there is a significant increase. One-fourth of cases in children occurred in the last month.

How should parents be managing this increasing risk of transmission?

Anyone living in the household eligible to get vaccinated should get vaccinated because that’s one way to prevent bringing COVID into the household and exposing different individuals. People need to continue to use protection mitigation protocols, so definitely mask-wearing for kids old enough to wear a mask, some social distancing, good hand hygiene — the same stuff we’ve been talking about for the past 2.5 years. That hasn’t gone away, and you need to continue to do that, especially if you’re around these kids that are too young to be vaccinated.

Last week the FDA was slated to make a decision regarding Pfizer’s vaccine for children between 6 months and 4 years of age, but they decided to delay the decision for at least 2 months. Why was it delayed?

The initial preliminary data that came out from clinical trials for kids 6 months to 5 years of age basically showed that kids between 2 and 4 years of age did not mount an adequate immune response to two doses of the vaccine. I think people need to remember the vaccine that was being tried was only 3 micrograms per dose, which is one-third of what the 5- to 11-year-olds get and one-tenth of what people 12 years and older get. After two doses, [kids between 2 and 4 years of age] did not mount a good immune response, whereas there was a good immune response in the youngest kids between 6 and 23 months of age.

I don’t know why Pfizer came out and said they were going to do this, but I think it was smart to delay this until there can be more data that is obtained. Because what they’re looking at doing now is giving a third dose of the 3-microgram vaccine about two months after the second dose to see whether or not the kids will develop an immune response, and we don’t have data on that yet.

Were there any red flags or troubling side effects in the trials you noted?

Kids tend to tolerate these vaccines better than adults. The side effect profile looks great. There are a few mild side effects. But you want a vaccine that’s also effective, and I think that’s where the holdup is here.

What does it mean that the vaccine is not working well against Omicron for this age group?

I think that it is premature to determine if the vaccine is not working well against Omicron in this age group. The current vaccines work well at protecting against severe disease, hospitalization, and deaths due to Omicron in the other age groups where the vaccine induces a robust immune response. This is what you want. The vaccines are not as protective against preventing mild disease or breakthrough disease.

Are you hopeful that the three-dose regimen, rather than the two-dose regimen, will be effective against Omicron and future variants?

It is hoped that the three-dose regimen will induce a robust and effective immune response compared to the two-dose regimen. If this is the case, there is no reason that the vaccine should not be effective against severe disease, hospitalization, and death caused by Omicron and future variants.

When do you realistically think vaccines will be available for this age group?

The data should be available from the end of March to early April, and we’ll have to go from there.

What don’t we know about COVID-19 in this population that you think we should be putting more resources into finding out?

We don’t know about long-term COVID in these kids, and that’s something we need to continue to study. Multisystem inflammatory syndrome in children (MIS-C) is something that’s a little bit of a black box, so I think that’s something else we need to study.

What should parents be doing to prepare?

One thing to really emphasize is that people need to be up-to-date not only on their COVID-19 vaccines, but also on their other routine vaccines. This pandemic has really done a number on routine vaccination rates in the pediatric population, and we need to bring those up to date before we see an outbreak of a vaccine-preventable disease on top of the COVID that continues to circulate.