A Delta Plane has been quarantined at Chicago Midway Airport.

CBS local reports that "serious medical problem with a passenger" has led to the quarantine.

Sources told CBS that the flight may have been traveling from Ghana and a passenger may have "some sort or rash and contagious disease".

ABC7 reports that emergency crews are on the runway and the Chicago Department of Public Health is working with the Centers for Disease Control.

The aircraft has been identified as Flight 3163 from Detroit.

UPDATE 6:43pm EST: Twitter user Kayla Maree Sanders appears to be on the flight. She says she has been told it is "not serious" and tweeted the following picture:





UPDATE 6:50 pm EST - Detroit Free Press has spoken to a passenger who says the Chicago Fire Department are looking at sick woman onboard. The woman has previously been traveling in Uganda, the passenger was told.

UPDATE 6:57 pm EST - ABC7 tweets:

ABC News: Delta says quarantined plane at Midway is clear — ABC 7 Chicago(@abc7chicago) April 26, 2012

UPDATE 7:06 ET - Detroit Free Press reports that the passengers have been released after 2 hours in quarantine. Fox News Chicago also reports the passengers are being let off the plane and normal airport operations are resuming.

UPDATE 7:51 ET - CDC thought it was MONKEYPOX! Here's the statement:

CDC received a report earlier this evening of a passenger on a plane at Midway Airport who had a rash. Since the passenger had been in Africa, a family member had reported concerns that the rash might be monkeypox. The passenger was evaluated by Chicago EmergencyMedical Services. medical staff at CDC and the Chicago Department of Public Health (CDPH) reviewed the case and, based on the patient’s symptoms and photographs of the rash, it does not appear that the signs and symptoms are consistent with a monkeypox infection. The ill passenger was advised to seek medical care and the rest of the passengers were released from the plane. CDC and CDPH believe there is very little risk to other passengers. However, out of an abundance of caution, the airline will be collecting contact information for other passengers should CDC need to contact them in the future.