Understanding COVID-19’s impact on children: MIS-C explained
By Primary Children's Hospital
Dec 21, 2020
Updated Oct 25, 2023
5 min read
COVID-19 continues to impact people of all ages, not only in Utah but across the world.
In the early stages of the pandemic, information regarding COVID-19’s impact on children was minimal, and children weren’t considered a vulnerable population. However, as medical professionals have become more familiar with this disease over the past several months, it is clear that children are susceptible to some potentially devastating side effects from COVID-19.
While most of the severe COVID-19 illnesses and deaths have occurred in adults, children are experiencing a serious complication known as Multisystem Inflammatory Syndrome, or MIS-C.
Typically, children who contract COVID-19 experience mild symptoms, or no symptoms at all. However, a small portion of children who are infected with COVID-19 end up developing MIS-C, a life-threatening condition that can affect a child’s heart, lungs, kidneys, brain, skin, and other organs.
Jason Lake, MD, infectious disease doctor at University of Utah Health and Primary Children’s Hospital, wants the public to realize that COVID-19 does impact children and steps need to be taken to reduce transmission.
“There’s this notion out there that kids can’t get really sick from COVID-19 and that’s just not true,” said Dr. Lake. “The scariest part is most kids we see with MIS-C are completely healthy with no pre-existing conditions.”
MIS-C typically doesn’t show up for four to six weeks after first being infected with COVID-19. Since April, Primary Children’s Hospital has seen nearly 20 cases of MIS-C, but doctors expect those numbers to rise after a sharp increase in COVID-19 infections statewide.
Madilyn Dayton of Wyoming nearly died after doctors discovered she had MIS-C.
Madilyn, who is 12 years old, had noticed she was getting unexplained rashes, headaches, and loss of appetite. Then on Oct. 28, 2020, she woke up and discovered she couldn’t move any part of her body and called for her mother, Marilyn.
“I knew she had been dehydrated so I thought if we go get her some fluids, they’ll figure out what’s wrong with her and we’ll be home in a couple of days,” said Marilyn. “I never had any idea about what was about to happen and how serious and fast this started threatening her life.”
Madilyn’s COVID-19 test came back negative, but doctors soon discovered she had antibodies, which means she was likely infected weeks before but was asymptomatic. No one else in her family had shown any signs of infection.
“I thought I was taking precautions, I thought I was doing the best I could to protect my family,” said Marilyn. “And that's what was hard for me as a mother. But that’s why we wanted to share our story, to help everyone realize we can all take better precautions and take this pandemic more seriously.”
Marilyn — like many others — didn’t think children could experience any negative impact from COVID-19.
“I thought it was only specific categories that are truly at high risk,” she said. “I had no idea that kids can be affected so severely.”
Madilyn first experienced a headache and body aches. A few days later she struggled to walk and had no appetite.
“I started getting rashes all over my body, and that’s when I know this wasn’t a normal sickness,” said Madilyn. “Then one morning I woke up and I couldn’t move at all.”
Madilyn says she remembers her mom taking her to Primary Children’s Hospital, and then waking up in the intensive care unit.
After spending six days in the hospital, Madilyn was able to go home but couldn’t return to school. Her doctors said she can’t play sports or other do other strenuous activity for three to six months to prevent potential permanent scarring of the heart.
“Seeing my daughter deteriorate so quickly was scary,” said Marilyn. “It made me realize that we need to be better, we need to be more careful, and we need to care what our actions are doing to others. We don’t know if we are asymptomatic and passing on this illness to others who are high-risk. We just need to care, and we need to be better, no matter what.”
MIS-C looks quite different from an acute COVID-19 infection and can look remarkably similar to other autoimmune or autoinflammatory conditions, such as Kawasaki disease. The most common symptoms of MIS-C are fever, stomachache, vomiting, diarrhea, and rash. The hallmark of MIS-C is a fever, accompanied by labs that show high levels of inflammation in the body.
One of the most commonly affected systems is the cardiovascular system, with nearly half of MIS-C patients facing decreased heart function and low blood pressure. Leaky heart valves, fluid around the heart, and enlargement of the coronary arteries have also been reported.
Diagnosing MIS-C can be somewhat difficult since its symptoms mimic other autoimmune disorders, but doctors are committed to learning all they can from every single case.
“The most important thing is that we remain aware of MIS-C so that we can recognize it and treat it properly,” said Erin Treemarcki, a pediatric rheumatologist at University Health.
Steroids and anti-inflammatory medications are used to treat MIS-C. Over half of the children and young adults with MIS-C average six days in the hospital, with five of these days spent in the ICU. Levels of inflammation are monitored to help determine when medications and dosage amounts can be safely reduced.
Many of the medications used to treat MIS-C are immunosuppressants, drugs that put patients at an increased risk for infection. This added risk can delay their return to regular school or extracurricular activities. Beyond the medications, the ongoing nature of treatment — multiple follow-up appointments and blood draws — impacts the lives of these young patients, as most are previously healthy children with no pre-existing conditions.
Most patients respond well to treatment, and while it is rare for a child to die from COVID-19 or MIS-C, doctors are worried about the impacts on a child’s future health.