When the COVID-19 pandemic began, doctors had little information about what recovery would look like for children months or years after infection.
Now, one of the largest and most comprehensive pediatric COVID-19 studies is beginning to provide answers.
The Pediatric COVID Outcomes Study (PECOS), a collaboration between Children's National Hospital and the National Institutes of Health, enrolled over 1,000 children and adolescents and followed them over time, comparing those who had COVID-19 with a carefully screened group that had never been infected.
Unlike COVID outcomes studies that use retrospective reviews of medical records, this prospective study relies on detailed evaluations, physical exams, surveys, and testing of participants in person.
The study has produced a series of papers examining long-term symptoms, behavioral health, and cardiac outcomes. Together, they offer one of the clearest pictures yet of COVID-19's lasting effects on children and raise important questions about how children's hospitals care for patients whose symptoms persist long after an infection has resolved.
Here are five key takeaways from the research so far, according the co-principal investigator Roberta DeBiasi, MD, chief of pediatric infectious diseases at Children’s National Hospital.
1. Long COVID in children is real
The PECOS team identified a group of children who experienced persistent symptoms after COVID-19 infection. Those symptoms varied by age and changed over time, but for some children they affected far more than physical health.
Fatigue can make it difficult to get through a school day. Headaches can interfere with concentration. Exercise intolerance can keep children from participating in sports and other activities that are central to childhood.
“There is a subset of kids who have symptoms which affect their life,” DeBiasi said. “Particularly when they’re at a time of life when they should be attending school and being with their friends and developing socially and doing sports.”
For families searching for answers, those symptoms are often difficult to explain and difficult to connect to a single diagnosis.
2. Long COVID doesn’t look the same in every child
Long COVID appears differently across age groups and may evolve over time.
Researchers identified 20 symptoms that were more common among children who had recovered from their initial COVID-19 infection than among those who were not infected. Among the most frequently reported:
- Fatigue
- Headaches
- Gastrointestinal problems
- Persistent cough
- Difficulties with concentration or memory
- Muscle and joint pain
- Trouble sleeping
Symptoms seen in younger children — such as prolonged fever or dry persistent cough — often differed from those reported by adolescents and young adults. And some symptoms improved over time while others persisted or appeared later.
This vast spectrum of symptom presentation is one reason diagnosing and treating these children can be challenging.
3. The pandemic affected an entire generation’s mental health
One finding surprised DeBiasi and her colleagues.
Children who had COVID-19 reported more physical symptoms, more pain, more sleep problems, and greater difficulty with cognitive functioning than children who had not been infected.
But rates of anxiety and depression were similar in both groups.
That suggests many of the mental health challenges children experienced over the past several years were not caused by infection alone.
“The pandemic has affected all children,” DeBiasi said.
4. COVID-19 doesn't cause lasting heart problems
Parents often worry COVID-19 might leave lasting damage to a child’s heart.
Researchers specifically looked for evidence of that and found none.
Even children who reported symptoms such as chest pain, fatigue, or racing heartbeats generally had normal cardiac function on advanced testing, including an echocardiogram. Additional detailed analysis of EKG and cardiac MRI data is in progress.
For families who continue to worry about long-term heart damage, DeBiasi says these findings should provide reassurance.
5. Children with post-infection symptoms need coordinated care
Many of the challenges facing children with long COVID are familiar to clinicians who care for patients with other infection-associated chronic illnesses, including post-treatment Lyme disease syndrome, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), PANS/PANDAS, and other conditions that can persist after an infection has resolved.
These patients don’t fit neatly into a single specialty. A child may see a cardiologist for chest pain, a neurologist for headaches, a gastroenterologist for abdominal symptoms, and a psychologist for cognitive concerns. Families can spend months moving through the health care system without anyone looking at the whole picture.
"We hear over and over from these families that people don't believe them," she said.
DeBiasi sees an opportunity to recognize infection-associated chronic illness as a clinical category worthy of dedicated expertise, research, and care models.
What comes next?
The next challenge, DeBiasi said, is understanding why some children recover quickly while others continue to struggle months or years after infection. Researchers are now using the study’s clinical data and biological samples to search for those answers.
In the meantime, DeBiasi hopes the research helps clinicians and families recognize an important reality: While most children recover completely from COVID-19, those who don’t deserve to be heard, supported, and studied.
“Resources that are applied to adults should be equally applied to kids,” DeBiasi said. “There’s a specific group of children who need our attention.”
