Why Aren’t COVID-19 Vaccines Being Tested in Children?

Dr. Paul Offit explains why COVID-19 vaccines were not initially tested in children and how it will be determined as to when those 18 years and younger will be recommended to receive these vaccines.


Paul Offit, MD: Hi, my name is Paul Offit from the Vaccine Education Center at the Children's Hospital of Philadelphia. One question parents have about these COVID-19 vaccines is, “Why aren't they being tested in children?” Certainly it's true that the initial trials that are being done by companies looking at COVID-19 vaccines are being tested in those over 18 years of age. But I think the short answer is that eventually these vaccines will be tested in children. The most probable reason for why they aren't initially being tested in children is that although people less than 21 years of age in the United States make up about 26% of the United States population, that group only accounts for 0.08% of the deaths.

But the fact is, is that the number of children who have died this year from COVID-19 is really about the same as the number of children who have died from influenza. So, I think it is important to immunize children. That's going to happen in one of two ways. Either children over time, over the next year or two, will be formally tested in the same way that adults are tested, which is that some children will get a vaccine, some children will get a placebo, and you'll see to what extent the vaccine works. I think the more likely way this is going to play out though, is that when we do these studies in adults and we find out that some adults are protected by the vaccine and some aren't, and that the reason that some are protected and others aren't is that the ones who were protected have a certain level of virus neutralizing antibodies in their bloodstream, then I think we'd be able to do something called immuno-bridging studies, which is to say that you immunize children, you see whether or not that particular vaccine induces the immune response that you knew was protective in adults, and then go forward from there.

So, we'll see how this plays out. But I think in the end, children will be tested to make sure that these vaccines are safe and effective in them because I don't think there is any other way we can give them those vaccines otherwise.

Thank you.

Related Centers and Programs: Vaccine Education Center

Last Reviewed on Nov 23, 2020