The patients, ages 2 to 15 years, were hospitalized from April 17 to May 1, according to the alert.
Several tested positive for Covid-19 or had positive antibody tests.
Symptoms similar to Kawasaki Disease
Kawasaki disease causes inflammation in the walls of the arteries and can limit blood flow to the heart. It is usually treatable and most children recover without serious problems, but it can be deadly.
At least five of the cases required a ventilator and more than half of the patients required blood pressure support. So far, no fatalities have been reported among the New York City patients.
Similar cases have also been reported in Italy and Spain.