Norovirus is the suspected cause of an illness contracted this week by travelers at O’Hare International Airport.
At least nine people were taken to the hospital Monday after they began throwing up in the international terminal around 11 p.m.
Chicago Fire Department officials said the people were part of a tour group of about 50 that had been on a bus trip through the Midwest. They came to O'Hare to board a Scandinavian airline to Copenhagen.
Investigators’ initial primary diagnosis is the norovirus, a contagious virus that causes vomiting and diarrhea and is spread through food or contact with infected people, according to the Daily Herald.
They believe the virus was contracted outside of Chicago, but officials are unable to confirm its diagnosis at this time, the Daily Herald reports.
Each of the nine sickened passengers was taken by ambulance to area hospitals. They were described as being in good condition but very sick with symptoms of vomiting and upset stomachs.
The remaining tour group members were allowed on the plane, but once on board, another person started getting sick, fire officials said. The captain then stopped the flight and decided to let everyone from the tour group off the plane.
Some went to the hospital and others received vouchers for area hotels.