Digital ads alerting parents to the symptoms of the inflammatory condition in children will start Wednesday, de Blasio said, and ads on radio and TV, on bus shelters, and in community newspapers will follow.
"We have to rapidly inform families all over the city," the mayor said.
Pediatric Multi-System Inflammatory Syndrome (PMIS) affects blood vessels and organs and has symptoms including prolonged fever, abdominal pain and vomiting. Three children diagnosed with the syndrome have died in New York state, including one in New York City.
Of the 82 children diagnosed with pediatric multisystem inflammatory syndrome in the city, 53 have tested positive either for COVID-19 or for antibodies for the disease, de Blasio said.
The Associated Press contributed to this report.
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