By Beth Germano

BOSTON (CBS) – It’s a mysterious and so far unexplained infection, affecting children in the midst of the coronavirus pandemic. “This is a post viral response where the body’s immune system is causing persistent fevers and inflammation,” said Dr. Jeffrey Burns, chief of critical care at Boston’s Children’s Hospital.

Burns said they are symptoms resemble Kawasaki disease and first started showing up weeks ago in young patients in European countries heavily impacted by covid-19 and New York where a health warning has been issued.

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“There’s no question we’re seeing a cluster of patients and we do think it’s related to covid-19,” said Dr. Burns.

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The sick children have either tested positive for covid-19, which has been rare in the United States, or have shown antibodies for the virus. Children’s Hospital is treating four suspected cases as doctors say it looks like a reaction four to six weeks after being exposed.

Nancy O’Connor’s son Jake was 10 years old when he contracted Kawasaki disease back in 2007 with spiking fevers. She says at the time it was difficult to diagnose. “He had weird rashes all over him and it just got worse and worse,” O’Connor said. “I want people to know about it again because it was so frustrating to go through as a parent.”

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It’s not the first time a disease has caused a post-viral reaction, but doctors say with so much still unknown about covid-19 they’re not trying to better understand it.

Beth Germano