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COVID-19 may be causing long-term symptoms in children, according to a preprint posted on MedArxiv. The study, which has yet to be peer reviewed, provides preliminary evidence that children can suffer from long-COVID as can adults, with symptoms lasting for months after their initial SARS-CoV-2 infection.
Until now, there have been few data on long-COVID in children, although persistent symptoms among adults have been increasingly reported since the pandemic started. One large cohort study showed that 76% of adults reported at least one persistent symptom 6 months after SARS-CoV-2 infection.
To learn more about long-term effects of SARS-CoV-2 infection in children, researchers surveyed caregivers of 129 patients in Rome, Italy. The patients were younger than 18 years and had a confirmed COVID-19 diagnosis. The researchers used a questionnaire developed by the ISARIC Global COVID-19 follow-up working group ― an international group of researchers whose initial studies concerned adult long-COVID. The questionnaire asks about respiratory symptoms, fatigue, nasal congestion, muscle pain, and other symptoms.
More than 50% of the children had at least one symptom that persisted 4 months or longer after their diagnosis, and nearly a quarter (22.5%) reported three or more such symptoms. Although patients who were symptomatic or were hospitalized during acute infection were more likely to report persistent problems, some children who were asymptomatic during the acute phase of COVID also described having symptoms several months later. Of the patients who experienced long-COVID, 42% reported that their extended symptoms interfered with everyday life.
Lead author Danio Buonsenso, MD, told Medscape Medical News that he had not expected to find so many patients experiencing long-COVID in the first cohort he examined. Buonsenso is a pediatric infectious disease physician at the same institution in Rome that first reported on adult long-COVID. During the summer, after reading his colleagues’ work, he became curious whether children are affected the same way. “Then I saw my first case in September,” he said. He’s now working with a network of pediatricians in Italy to collect more data.
But pediatric infectious disease specialist Danielle Zerr, MD, MPH, is hesitant about interpreting the newly reported data, inasmuch as the study lacked a control group. “I would be very cautious about making conclusions with these data,” Zerr, a physician at Seattle Children’s Hospital, Seattle, Washington, told Medscape Medical News. “Nasal congestion any time of any year is common in kids.” In addition, fatigue is difficult to assess during a year when children weren’t going outside. “A control population is really important when you’re talking about nonspecific signs and symptoms,” she said. Otherwise, it’s hard to know what is normal, especially in an unusual time such as during the current pandemic.
As a way to establish some sort of baseline, the authors asked parents to recall their child’s health status before becoming infected with SARS-CoV-2. But asking parents and patients to compare their symptoms or energy levels at the time of the survey to pre-COVID levels (which may have been 4 or more months prior) may result in recall bias, said Lara Danziger-Isakov, MD, pediatric infectious disease specialist at Cincinnati Children’s Hospital, Cincinnati, Ohio.
On top of that, she said, “this is a small population.” It’s a substantive population, but considering that several million children have been affected, “we really need to understand what the true penetration of symptoms is,” Danziger-Isakov said, and that requires studying more than 129 patients.
In addition, she notes that it’s not clear how the patients in the study were selected. The preprint doesn’t provide those details, and it’s possible that the study design could have selected for patients with extended symptoms. If this is the case, the true prevalence of long-COVID could be much lower than the 50% reported in the study.
“No one is an expert in long-COVID at this point. It’s an emerging clinical syndrome,” Danziger-Isakov said. In addition, this new study lacks some key details that will hopefully be addressed in the peer-review process. But it’s still important work, she said. “It’s waving a flag to say we need to pay attention to this and do more investigation,” Danziger-Isakov said.
And researchers are doing that. Buonsenso and his team are collecting data on a much larger cohort of patients and are following them over time to take more objective measurements. At least one clinical trial by the National Institutes of Health is investigating long-term effects of COVID in adults, and another is studying severe COVID complications in children.
“I look forward to those results,” Zerr said. In the meantime, however, physicians shouldn’t conclude that 50% of pediatric COVID patients will have long-COVID, she says. The current data are important and make it clear that long-COVID is occurring in children. And that’s a start to identifying the syndrome and developing management strategies.