Most U.S. children with a severe inflammatory disease linked to the coronavirus had initial Covid-19 infections with no symptoms or only mild ones, new U.S. research shows.
The unusual condition after infection tends to be milder in children who were sicker with Covid-19, although more than half of the affected young children received intensive hospital care, according to an analysis by the Federal Centers for Disease Control and Prevention. Was published Tuesday in JAMA Pediatrics. .
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The study represents the largest analysis to date of U.S. cases of multisystem inflammatory syndrome in children and reinforces 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 younger than 15, but the study included up to 20 years of age.
Investigations into cases took place two to five weeks after the Covid-19 peaks and followed the spread of initial infections from urban to rural areas, the researchers said. More recent CDC data indicate that there is again an emerging peak in the pediatric condition consistent with the trend.
The CDC’s cases on March 29 totaled 3,185 and included 36 deaths. State reports are not always timely, so it is uncertain how many U.S. children have developed the disease since the study ended.
Most children who have had Covid-19 do not develop the disease after infection. Nearly 3.5 million American children and teens tested positive for Covid-19, according to data compiled by the American Academy of Pediatrics and the Children’s Hospital Association.
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The condition was first reported in Europe in the late winter and spring of last year. Some cases, especially cases 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 Committee on Infectious Diseases at the Pediatric Academy, said that the inflammatory condition usually causes children to get sick very quickly, but that most respond very well to treatment and the vast majority recover completely.
Treatments may include steroids and other medications that may reduce inflammation.
The best way to prevent this is to prevent Covid-19 infections, ” which do the vaccines very well, ” 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 children affected. Nearly one-third had heart inflammation or other heart involvement. These symptoms are least common in children up to 4 years of age, who are also less likely to require intensive care than older children.
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