New York Gov. Andrew Cuomo (D) confirmed that at least three children have died from a new pediatric multi-system inflammatory syndrome likely linked to COVID-19. As many as 93 other children have presented symptoms of the mysterious illness.

“The illness has taken the lives of three young New Yorkers,” Cuomo said during his Saturday briefing. “This is new. This is developing.”

The toxic-shock-like inflammation affects the skin, the eyes, blood vessels and the heart, and can require some children to be ventilated.

“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 system,” Cuomo said Saturday.

New York City Mayor Bill de Blasio said Tuesday the city had confirmed 52 cases of pediatric multi-system inflammatory syndrome, and 10 cases were pending. Of those, 25 of the children tested positive for COVID-19 and 22 had antibodies.

The city’s top doctor, Oxiris Barbot, told parents to be on the lookout for telling symptoms of the syndrome during the governor’s briefing.

“If [your child has] a fever, their energy level is off, their appetite is off, they’re developing a rash, their lips look extra red, their tongue is looking extra red, those are the early signs that we want parents not to discount them and say ‘oh they’ll be better tomorrow’ but to reach out to your pediatrician, have that conversation and then do the testing if your pediatrician thinks its indicated,” Barbot said.

Doctors in New York say children are not presenting symptoms until 4 to 6 weeks after exposure to COVID-19.

Cuomo called the appearance of the new illness “every parent’s nightmare.”

“We were laboring under the impression that young people were not affected by Covid-19, and that was actually good news,” Cuomo said. “We still have a lot to learn about this virus. It is very possible that this has been going on for several weeks and it hasn’t been diagnosed as related to Covid.”

Several of the symptoms resemble a rare childhood illness called the Kawasaki disease, which can lead to inflammation of blood vessels. However, doctors are noting slight differences in the symptoms.

While Kawasaki disease can produce coronary aneurysms when left untreated, the new syndrome seems to mainly produce inflammation of coronary arteries and other blood vessels.

The New York State Department of Health is working with the Center for Disease Control and Prevention to develop national criteria for medical systems to help them identify, track and respond to help children exhibiting symptoms, Cuomo said.

A few cases have been reported in other states, including Connecticut, Louisiana, Mississippi and California. At least 50 cases have been reported in European countries, including the United Kingdom, France, Switzerland, Spain and Italy.

President Donald Trump briefly addressed the mysterious COVID-19-related syndrome, saying “we’re looking at it very closely.”

“We’re studying that very closely … we’ve seen this for quite a while. It’s been very rare, but we’re looking at it very closely,” Trump said.

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