ATLANTA - When we think about COVID-19, most of us automatically think of cough, or fever, or shortness of breath.
But, a small number of U.S. children are developing severe inflammation, weeks after their illness, and doctors are racing to figure out why.
Dr. David Kimberlin, Co-Director of the Pediatric Infectious Disease Department at the University of Alabama at Birmingham School of Medicine, says how the virus that causes COVID-19 behaves in children is one of the most intriguing mysteries of this pandemic.
"Children, for reasons that are not clear, do better with this virus,” Dr. Kimberlin says. “I don't know why that is. None of us know why that is."
Only about 2% of confirmed COVID-19 infections in the U.S. are in children.
Youngsters tend to have milder symptoms than adults if they have any symptoms at all.
Yet, for the last few weeks, across the US, hospitals like Children's Healthcare of Atlanta have been seeing small clusters of children coming in with signs of severe inflammation throughout their bodies.
Most, but not all, had tested positive for COVID-19 in the weeks before their hospitalizations.
Dr. Kwang Kim, Director of Pediatric Infectious Diseases at Johns Hopkins School of Medicine in Baltimore, has seen 3 or 4 children with the disorder, known as "multisystem inflammatory syndrome in children,” or MIS-C.
The complications first surfaced in late April and early May, Kim says.
There are still many unknowns.
"We are trying to learn as much as possible, about, one, is this truly a new syndrome,” Dr. Kim says. “(And), Two, is there any connection with the SARS-Cov-2 infection? And three, why this occurs in children."
Dr. Kimberlin says there have been additional cases reported in Europe and Britain, where two-thirds of the children who developed severe inflammation tested positive for COVID-19, either on a diagnostic test or through an antibody blood test that indicates exposure to the virus in the past.
He says the inflammatory syndrome appears to be linked to COVID-19, but it is not clear if the infection is triggering the inflammation.
"Is it the virus itself that's causing this, or is it the body's reaction to the virus that is causing this,” Kimberlin asks.
New York, the epicenter of the U.S. novel coronavirus outbreak, has reported 147 cases in children, including 3 deaths.
Dr. Kim says the symptoms look a lot like both Kawasaki disease, an inflammatory disease seen in young children under 5, and toxic shock syndrome.
"The cases we have seen, oftentimes, they present with more than just fever: fever with a rash, fever with conjunctivitis, or fever with swelling of the palms and toes."
Children with this type of hyper inflammation can also have abdominal pain and swollen lymph nodes.
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Late last week, the CDC issued an alert for pediatricians to be on the lookout for children with fever and signs of inflammation, especially those who have tested positive for COVID-19 in recent weeks.
They come in very, very sick,” Dr. Kimberlin says. “These children end up in the intensive care unit, and they get there very quickly. So, they'll come in with low blood pressure. They may have a rash, they may have belly pain, they may have manifestations of heart failure. From a parent’s standpoint, all they need to know, and they would know this before the pandemic, all they need to know is, my child is very sick."
Both Dr. Kim and Dr. Kimberlin urge parents to get help quickly if they see signs of this inflammatory syndrome, and they're asking pediatricians to keep this on their radar screen.
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