At least 3 New York children have died from a mysterious, possibly coronavirus-related inflammatory illness which can cause heart trouble

• New York Governor Andrew Cuomo on Saturday said at least three children have died in New York from a rare condition that's being linked to the coronavirus.
• The illness, called "pediatric multisystem inflammatory syndrome" has symptoms similar to the Kawasaki disease and toxic-shock syndrome, including fever, rash, stomach pain, diarrhea, and vomiting.
• Children in at least six European countries have also come down with similar symptoms recently.
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Three children who had COVID-19 in New York are dead, after they developed rare heart issues that may be linked to the novel coronavirus.

"The illness has taken the lives of three young New Yorkers," Governor Cuomo said at a news conference on Saturday. All three kids were under 10 years old.

The state is now investigating 73 cases of the mysterious illness, which health officials are calling "pediatric multisystem inflammatory syndrome."

"As it turns out, these children happened to have the COVID antibodies, or be positive for COVID, but those were not the symptoms they showed when they came into the hospital," Cuomo said.

"It's not a respiratory illness, they're not in respiratory distress, and I think that's one of the reasons why this may be getting discovered this far into the process. It's more an inflammation of the blood vessels, which can then cause problems with their heart."

The syndrome's symptoms are similar to Kawasaki disease, a condition that affects arteries to the heart, and toxic shock.

"It is very possible that this has been going on for several weeks — and it hasn't been diagnosed as related to COVID," Cuomo said.

The New York state health department, in coordination with the Centers for Disease Control and Prevention, is now developing national criteria for identifying the illness, so other states and hospitals across the US can investigate whether they have cases, too. New York is also starting a genome sequencing study to learn more about what might be making certain toddlers and elementary school kids susceptible to this syndrome.

"If your child is experiencing a persistent fever, rash, abdominal pain or vomiting, call your doctor right away," New York City mayor Bill de Blasio tweeted on May 5, before any of the pediatric deaths had been reported.

Kids have been thought to be less susceptible to some of the coronavirus' most devastating and deadly complications, but the new reports of illnesses and deaths, while still very rare, suggest children may suffer some COVID-19-related complications later on, which the virus might have triggered.

"We cannot say universally that it's a mild disease in children," the World Health Organization's Maria Van Kerkhove said during a press conference on May 1. "But the vast majority of children who have been identified as having COVID-19 have had mild disease."