Most children with a severe inflammatory disease related to the coronavirus had initial COVID-19 infections with no or only mild symptoms, new US research shows.
The unusual post-infection condition tends to be milder in children who were sicker with COVID-19, although more than half of the affected youths received intensive hospital care, according to an analysis. by the federal Centers for Disease Control and Prevention, published Tuesday in JAMA Pediatrics.
The study represents the largest analysis to date of US cases of multisystem inflammatory syndrome in children and supports evidence that it is a delayed immune response to COVID-19. The study included nearly 1,800 cases reported to the CDC from March 2020 to mid-January. Most were in children less than 15 years of age, but the study included up to the age of 20 years.
Rises in cases have occurred two to five weeks after COVID-19 peaks and have followed the spread of initial infections from urban to rural areas, the researchers said. More recent CDC data indicates that there is a new spike in the pediatric condition consistent with that trend.
State-reported cases through March 29 totaled 3,185 and included 36 deaths, the CDC’s website shows. State reports aren’t always current, so it’s uncertain how many American children have developed the disease since the investigation ended.
Most children who have had COVID-19 do not develop the disease after infection. According to data from the American Academy of Pediatrics and the Children’s Hospital Association, nearly 3.5 million American children and teens have tested positive for COVID-19.
The condition was first reported in Europe in the late winter and spring of last year. Some cases, especially those following silent, undiagnosed COVID-19 infections, can be mistaken for Kawasaki disease, a rare condition that can cause red skin, swelling, and heart problems.
Dr. Sean O’Leary, vice chair of the Pediatrics College’s Infectious Diseases Committee, said the inflammatory condition usually causes children to get very sick very quickly, but that most “ respond very well to treatment and that the vast majority get completely better. ”
Treatments can include steroids and other drugs that can reduce inflammation.
The best way to avoid this is to prevent COVID-19 infections, ” and those vaccines are doing a really good job, ” he said. COVID-19 vaccine studies in children are ongoing.
In the CDC analysis, fever was one of the most common symptoms. Abdominal pain, vomiting, diarrhea and red skin rash occurred in at least half of the affected children. Nearly a third had an infection of the heart or some other heart condition. These symptoms were least common in children up to 4 years of age, who also required intensive care less often than older children.
Follow AP Medical Writer Lindsey Tanner at @LindseyTanner.
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