By Stephanie Stahl

PHILADELPHIA (CBS) — Moderna will be testing its vaccine on children, and Children’s Hospital of Philadelphia will be enrolling patients for the study called KidCOVE. Also, from CHOP, there is new research on a rare but severe reaction to COVID-19 in some children.

New Jersey was hit hard and early by this syndrome in children. The CDC says cases have been increasing around the country.

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The new research from CHOP is leading to better treatments for children who have this severe reaction to COVID.

Lauren Grant, a nurse and COVID-19 survivor, thought she’d seen the worst of the virus — until a day care texted her a photo of her 5-month-old daughter, Madelyn.

Madelyn’s hands and feet were blue.

“It was absolutely terrifying,” Grant said. “My first instinct as a mother was, what’s going on? And then my second instinct, as a nurse, is she’s not getting enough oxygen. My husband and I were just sitting there sobbing because we just didn’t know if she was going to make it or not.”

Madelyn had recently recovered from COVID-19 but then developed a rare complication called multi-system inflammatory syndrome in children, or MIS-C.

“A lot of the body’s reaction to the previous infection causes it to ramp up and cause lots of inflammation and kind of get stuck,” Dr. Heather Daniels, pediatrician, said.

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New research from Children’s Hospital of Philadelphia on MIS-C indicates patients have a supercharged immune response.

“The immune activation that we see in children can actually look very much like the immune activation that we see in some of the sickest adults,” Dr. Laura Vella with CHOP said. “But what’s fascinating is that these children are not adults. Their syndrome is actually very different than severe adult COVID-19.”

Vella says the finding will help doctors further improve treatments for children and adults.

Madelyn was hospitalized for 10 days, but the treatments, including steroids, to reduce inflammation eventually worked.

“I feel like we were really lucky in that sense that Maddie didn’t have to be put on a ventilator,” Grant said, “and I think from what I’ve read so far is catching this early enough, so it doesn’t get to that point and that’s why it’s super important to be able to recognize these symptoms in kids.”

Children who have prolonged flu-like symptoms should be checked by a doctor.

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Doctors say COVID-19 is generally less severe in most children, but until a pediatric vaccine is approved for kids, they should take precautions. Wearing a mask is especially important.

Stephanie Stahl