Young children haven’t been included in COVID-19 vaccine clinical trials. Here’s why that concerns some doctors.

SAN ANTONIOEditor’s note: This content was created exclusively for KSAT Explains, a weekly streaming show that dives deep into the biggest issues facing San Antonio and South Texas. Watch past episodes here and download the free KSAT-TV app to stay up on the latest.

Over the course of the past year, we’ve learned a lot about COVID-19, the disease caused by the novel coronavirus. And while there is still a lot left to learn, we now know that it does affect children.

COVID-19 can cause a range of symptoms in children, from none at all to severe respiratory problems. Some have even died from the illness.

And while researchers believe children may not spread the coronavirus as widely as adults, it is still possible, particularly in teenagers.

But despite what we know about the virus’ impact on children, there won’t be a vaccine for them right away. That’s because they weren’t included in the initial clinical trials.

Pfizer included children in some later trials and Moderna announced in December they would begin to incorporate children over the age of 12 in its clinical trials. But pediatricians across the country say it’s past time to prioritize kids of all ages.

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Dr. Mandie Svatek, a pediatric specialist at UT Health San Antonio, said there are a lot of reasons why it’s important that children younger than 12 be included in clinical trials sooner rather than later.

One of the reasons: children have immune systems that are different from those of adults.

“Children aren’t small adults,” Svatek said. “It’s good that they are testing children 12 and above. But we still have to think about even the younger children where their immune system can be different.”

There are obvious concerns when it comes to testing on children. But Svatek said that these clinical trials have been conducted safely.

“The FDA is assuring, and the scientists that are testing the vaccines are assuring, even though we’re going fast, we can still do things the right way,” Svatek said. “It’s time, and it was time months ago to start testing on children that are even younger than 12.”

The effect of COVID-19 on children goes beyond just the threat of infection. There is also a social and educational risk of them falling behind because of disruptions to in-person learning and limited interactions with their peers.

“If they get sick with Covid, or they have exposure and they’re quarantined, what does that mean for the future of their learning?” Svatek said. “Does that delay any sort of learning and that opportunity to further their career in school and then further themselves as they go along?”

In a September letter to the Department of Health and Human Services, the president of the American Academy of Pediatrics urged the inclusion of children in clinical trials. The letter referenced both the physical and social effects of the pandemic on children:

On Friday, the Food and Drug Administration issued an Emergency Use Authorization for the Pfizer-BioNTech COVID-19 Vaccine for people 16 years of age and older.

MORE: Coronavirus and kids: San Antonio epidemiologist breaks down risks, school safety

About the Authors:

Lexi Salazar produces KSAT Explains, a weekly, in-depth streaming show that digs into the most important issues facing San Antonio. She previously produced the News at 9, San Antonio's first streaming-only news program.

Valerie Gomez is the lead video editor and graphic artist for KSAT Explains. Before starting at KSAT in 2017, she worked as a video editor for KENS 5 and KVUE in Austin. She graduated from Texas State University in 2013 with a bachelor's in mass communication and is a product of SAISD and the South Side of San Antonio. She loves Jeff Goldblum.