After COVID-19, Kids Can Develop MIS-C: Here Are the Signs

• Among children who get COVID-19, a small proportion develop multisystem inflammation syndrome (MIS-C).
• This serious complication can appear weeks after the initial infection.
• MIS-C causes widespread inflammation that can affect multiple tissues and organs.

While COVID-19 tends to be less severe in children than in adults, some kids do become seriously ill with the disease or related complications.

Among young people who contract the coronavirus, a small proportion develop multisystem inflammation syndrome in children (MIS-C). This serious complication can appear weeks after the initial infection.

“MIS-C is a postinfectious inflammatory condition, where your body’s immune system kind of goes into overdrive,” said Dr. Christina Johns, MEd, FAAP, a pediatric emergency physician and the senior medical adviser for PM Pediatrics in Lake Success, New York.

“The ripple effect of that means that there can be lots of inflammatory processes going on in many different organs,” she said.

In a study published last week in JAMA Network Open, researchers looked at 1 million cases of people under age 21 who contracted the coronavirus and later developed MIS-C.

“While it is rare complication — and the numbers from this new study certainly support that — it is not one without consequence. It is not a small deal to get MIS-C,” Johns said.