VALHALLA, N.Y. (CBSNewYork) — A Westchester County boy has died after coming down with an illness affecting dozens of children in New York State.

The 7-year-old boy died late last week at Maria Fareri Children’s Hospital in Valhalla. Dr. Michael Gewitz said he suffered neurological complications from what is now called pediatric multi-system inflammatory syndrome.

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Health officials said there have been 73 suspected cases of the illness statewide and investigators are doing a deep dive into the circumstances.

Gov. Andrew Cuomo shared an update Friday, announcing the death of a 5-year-old boy, who CBS2 later confirmed died at Mount Sinai Kravis Children’s Hospital.

“Right now we have a new issue that we’re looking at, which is something we’re just investigating now, but, while rare, we’re seeing some cases where children affected with the COVID virus can become ill with symptoms similar to the Kawasaki disease or Toxic Shock-like syndrome that literally causes inflammation in their blood vessels,” Cuomo said. “This past Thursday, a 5-year-old boy passed away from COVID-related complications, and the State Department of Health is investigating several other cases that presents similar circumstances.”

The hospital said in part, “We must emphasize that based on what we know thus far, it appears to be a very rare condition.”

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It’s still unclear exactly how the syndrome relates to the coronavirus.

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The Westchester boy tested positive for COVID-19 antibodies, meaning he was previously infected and had recovered, CBS2’s Tony Aiello reported.

“And we know that in some of the households parents or grandparents or others were diagnosed with COVID and were actually on the record being positive, and apparently the children did not develop symptoms until two to four days before presenting to the hospital for treatment,” said Dr. Dial Hewlett of the Westchester County Department of Health.

“This is very serious. The disease can be fatal, and we want to make sure everyone in Westchester County is aware to be on the lookout for symptoms that may lead to this,” County Executive George Latimer added.

Web Extra: Health Advisory On Pediatric Multi-System Inflammatory Syndrome

Seek care immediately if a child has:

  • Prolonged fever (more than 5 days)
  • Difficulty feeding (infants) or is too sick to drink fluids
  • Severe abdominal pain, diarrhea, or vomiting
  • Change in skin color – becoming pale, patchy, and/or blue Trouble breathing or is breathing very quickly
  • Racing heart or chest pain
  • Decreased amount or frequency of urine Lethargy, irritability, or confusion

“So this is every parent’s nightmare, right? That your child may actually be affected by this virus. But it’s something we have to consider seriously now,” Gov. Cuomo said.

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In New Jersey, a 4-year-old child with underlying health issues has also died. It’s unclear if he was affected by the inflammatory syndrome, but there are a handful of other suspected cases in Garden State kids.

“It’s a virus that’s proving to be extremely challenging at every level,” Gov. Phil Murphy said.

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Dr. Gewitz said while COVID-19 is likely to infect a large number of children, “most of whom, at least many, are totally asymptomatic. This particular complication is relatively infrequent, unusual.”