An international study estimates the prevalence of prolonged Covid in children to be between 5% and 10% – much lower than estimates of more than a third of adults having prolonged Covid.
The findings, published Friday in the journal JAMA Network Open, also suggest that several factors may predict which children with Covid may have ongoing symptoms or develop new symptoms within 90 days of infection.
They had seven or more symptoms in the early stages of the disease and were hospitalized for more than two days. Age was also a factor: Long-term symptoms were more common in children 14 and older.
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“This identifies the children we need to be in close contact with” because they are recovering after a positive Covid test, said one of the study’s authors, Dr. Nathan Kuppermann, professor of emergency medicine and pediatrics at the University of California, Davis School of Medicine.
In the study, Kupperman and a team of researchers interviewed parents and their children who were brought to the emergency room for Covid. Interviews were conducted two weeks and then three months after the emergency room visit. The study participants came from eight countries: Argentina, Canada, Costa Rica, Italy, Paraguay, Singapore, Spain, and the United States. Most of them were from the USA
The project included 1,884 children diagnosed with Covid and admitted to the emergency department between March 2020 and the end of January 2021, as well as 1,701 children who did not have Covid but sought emergency care for other reasons.
About 1 in 10, or 9.8%, of children with Covid-19 who were admitted to hospital reported ongoing symptoms – usually fatigue, cough and shortness of breath – three months later.
Of the Covid-positive children sent home directly from the ER, 4.6% continued to have symptoms 90 days later, the report said.
The number of children testing positive for Covid has been increasing in recent months. More than 75,000 new pediatric cases were reported in the week ending July 14, according to the American Academy of Pediatrics. That’s more than the 68,000 cases reported last week.
About 5% to 10% of children with Covid in the study match what infectious disease specialists see in their clinics, said Dr. Roberta DeBiasi, chief of infectious diseases at National Children’s Hospital in Washington, D.C.
He said the message to parents should be one of reassurance.
“If your child gets Covid, it’s likely to be a mild illness,” DeBiasi said, “and they won’t have long-term symptoms.”
There are several theories that suggest that older adolescents may have more long-term symptoms than younger children. This, Kuppermann, suggested that there may be more viral particles in the infectious system of teenagers.
However, it is better to say what teenagers are feeling.
“We’re relying on parents to report how their kids are doing,” Kuppermann said. “A 2-year-old won’t tell you about the Covid fog, and I don’t believe their parents can identify the Covid fog as well as a 15-year-old.”
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The study also found that about 5% of children hospitalized for reasons other than Covid had persistent symptoms such as fatigue, difficulty concentrating or abdominal pain after 90 days.
This suggests that perhaps other factors related to the pandemic – lockdowns, isolation, remote learning – may also be playing a role in ongoing symptoms.
“Teenagers have a lot going on in their lives at once,” Kuppermann said. “They’re isolated from their friends. They’re not in school.”
“The consequences of Covid should include not only Covid infections, but a significant increase in mental health problems,” he said.
Persistent symptoms in children, including fatigue and trouble concentrating, deserve a doctor’s attention, DeBiasi said, whether the cause is Covid or something else.
“There’s a lot of different things that we’re seeing, like not thinking clearly, having trouble with school, anxiety, depression,” he said.
“We want them to get the care they need and not feel like they’re being fired,” DeBiasi said. “We don’t want these kids to suffer.”
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