It was reported in the news this AM that all of them had passengers who were returning from the affected areas.
There was a plane from Dubai that landed at JFK on Sunday.
There were two AA planes that landed in Philly on Monday. One of those was from Paris. The other was from Munich.
Hope this helps.
"Both of today’s flights were on American Airlines: one from Munich and another from Paris. They landed at Philadelphia International Airport with about a dozen people in total on board who felt sick, according to a statement from the airport. "