Update, 9:52 p.m., May 6, 2020: 64 children in New York state have a mysterious inflammatory disease associated with the new coronavirus, the Department of Health said Wednesday.

NEW YORK - As COVID-19 ravaged the city in recent weeks, parents could at least take refuge in the fact that children were largely unscathed.

But the virus may have again sprung a surprise.

"If you’re a parent, I want you to listen carefully,” said Mayor Bill de Blasio said during his daily briefing Tuesday morning. “Something’s happened in the last few days that’s beginning to concern our health department.”

In the past few weeks, reports emerged from the U.K. of children with a multi-system inflammatory syndrome similar to a rare condition known as Kawasaki disease. Symptoms can include prolonged fever, rash, stomach pain, red eyes and lips, and swollen tongue.

In a bulletin issued Sunday, the city’s Department of Health and Mental Hygiene said 15 cases had been identified in New York City. Five of the children were put on ventilators; none have died. The city instructed all health care providers to immediately report patients under 21 with these symptoms.

"We are learning that even though children by and large are mildly affected when it comes to COVID-19,” said New York City Health Commissioner Dr. Oxiris Barbot. "There can be situations where they are more severely affected."

Dr. James Schneider is chief of pediatric critical care medicine at Cohen Children’s Medical Center in eastern Queens. He says he’s had 22 to 25 cases, with 15 children in intensive care. Those patients come from throughout the Northwell Health network, which has hospitals in Long Island and New York City.

"We’re seeing toddlers all the way through teens," Schneider said.

Almost all of them have tested positive either for COVID-19 or for antibodies.

"They all have evidence of either a current infection, a past infection, and also some of the blood tests that we see that goes along with acute hyper-active immune system that we know goes along with a coronavirual infection," Schneider said.
 
Health officials say early recognition is key, as there is well-established treatment for Kawasaki disease, though some children are showing particularly severe symptoms including heart conditions and low blood pressure. Doctors say they don’t yet understand the phenomenon, which is brand new - though still extremely rare.

"Although these children do get and can be very critically ill, it’s really important to understand that the vast majority of kids who get a coronaviral infection will never get this,” Schneider said.
 
While the number of affected children appears small, city health officials say they expect to identify more cases as word spreads of the illness and its possible link to coronavirus.