Multisystem Inflammatory Syndrome: What Can Happen When Kids Get COVID-19

A rare but potentially fatal condition poses an additional risk for the virus' youngest victims.

Dale Smith Former Associate Writer
Dale Smith is a former Associate Writer on the How-To team at CNET.
Dale Smith
3 min read
A boy wears a handmade mask to try to reduce transmission of COVID-19, the disease caused by the coronavirus.

A small percentage of children with COVID-19 develop a serious syndrome that can cause rashes, trouble breathing and even cardiac arrest.

Stephen Shankland/CNET

With mask mandates largely retired, questions still surround COVID 19, including its effects on children: Can kids get very sick with COVID-19 or are they "almost immune"? Do they transmit the disease less to others? Can some kids get Kawasaki's disease?

Some of the confusion stems from doctors' initial belief that the novel coronavirus doesn't typically affect kids as severely as adults. That view was upended by the discovery of an inflammatory condition related to COVID-19 in children that mirrored autoimmune disease symptoms and, in rare cases, could be deadly. The consensus remains that children are less likely to die from the coronavirus than adults are, but that doesn't mean they're in any way immune.

"The idea that COVID-19 is sparing of young people is just false," Dr. Lawrence C. Kleinman, a professor at Rutgers RWJ Medical School who coauthored a JAMA Pediatrics study on coronavirus in children, told Science Daily. "Parents need to continue to take the virus seriously."

This article is not intended to serve as medical advice. By drawing on available information from sources such as the US Centers for Disease Control and Prevention and World Health Organization, it examines what experts say about COVID-19 in children, including how sick they can become and how contagious they might be to the adults in their lives.

How common is MIS-C/PIMS?

As of March 28, 2022, the CDC reported  7,880 cases of MIS-C and 66 deaths. With more than 80 million coronavirus infections in the US, that makes it quite rare. And the vast majority of patients have responded well to treatment, with most having fully recovered. 
According to the CDC:

  • The median age of patients with MIS-C was 9 years old. Half of the patients were between the ages of 5 and 13.
  • Almost two-thirds (61%) of reported patients were male and more than half (57%) were Black or Latino.

What can happen to children with COVID-19?

Fortunately, in the vast majority of pediatric coronavirus cases, the prognosis appears to be very good. It's still believed that most kids don't get as sick as adults with COVID-19 -- in fact, many may show no symptoms at all.

However, a small minority of children with COVID-19 have been found to develop a potentially life-threatening condition called pediatric inflammatory multisystem syndrome (aka PIMS) or multisystem inflammatory syndrome in children (aka MIS-C).

What are the symptoms of this inflammatory syndrome?

Doctors have observed persistent fever, red eyes and skin rashes, as well as low blood pressure, inflammation, pale and sometimes blue lips and skin, difficulty breathing and lethargy

The most severe reports describe blood clots, chest pain, elevated heart rate and organ failure, including, in extreme cases, cardiac arrest. Children with the illness don't always complain of respiratory problems the way doctors have come to expect from COVID-19 patients. But beyond these and a few other symptoms, doctors concede little else is known for sure about the syndrome. All they say is certain is that it requires immediate medical attention

What survivors say MIS-C/PIMS felt like 

Knowledge about MIS-C remains limited, but some children who have recovered have talked to the media about their experiences. 

One teen MIS-C patient told the New York Times that it felt "like someone injected you with straight-up fire" when he was hospitalized for heart failure.  

A 12-year-old girl told the Washington Post she remembered having "weird" bluish lips and feeling "super tired" before doctors said she went into cardiac arrest.  

Another 12-year-old girl developed a blood clot that stopped her heart. "It felt like someone was stabbing my leg," she told NBC, which reported that it took 45 minutes of CPR to get her heart started again. 

Can children spread coronavirus, even if they're asymptomatic?

CDC report that examined an outbreak at one Georgia summer camp in 2020 suggested that the coronavirus was able to spread quickly and easily among the nearly 600 children, teens and adults at the camp. Of those tested, 76% were positive for the coronavirus. Notably, about 26% of those with COVID-19 were asymptomatic.

However, a follow-up commentary in the Journal of the American Academy of Pediatrics contended that children are far more likely to contract the coronavirus from adults than adults are from children. The authors concluded that children are not significant drivers of coronavirus community spread.
"Therefore, consideration should be paid toward strategies that allow schools to remain open, even during periods of COVID-19 spread," the wrote.

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.