Lise Sievers blames her recent trip to Africa for causing her Delta Air Lines plane to be grounded and quarantined at Chicago's Midway airport Thursday afternoon.

"I was visiting Uganda ... where I'm adopting two special needs kids. So we stayed at a hotel the other night and I think it left friends on my body. My son, who's four and a half, had pustules on him," Sievers said after deplaning Flight 3163.

The flight originated from Detroit, but passengers were kept on the plane outside Gate A7 for more than two hours after landing. From the sky, NBC Chicago's helicopter could see the aircraft on the ground, surrounded by medical and emergency personnel. 

"Since the passenger had been in Africa, a family member had reported concerns that the rash might be monkeypox," the Centers for Disease Control said in a statement obtained by NBC News. "The passenger was evaluated by Chicago Emergency Medical 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." 

"A couple of people came on board, went to one of the passengers, took photographs of her and of the sores that apparently existed. I couldn't tell from where I was sitting what those were," one passenger, David Grober, told NBC Chicago.

Read the original report at NBCChicago.com.

Another passenger on the plane posted a photo to Twitter showing an official wearing a face mask.

"Still in quarantine. They say it's not serious," Kayla Maree Sanders wrote in one Tweet.

Grober said the passengers were later given the all-clear, a fact later confirmed by The Centers for Disease Control in a statement:

"Passenger with rash illness has been examined, photos sent to CDC for analysis and based on info gathered has been released along with all other passengers."

The CDC added that "appropriate follow up" with Sievers was to come.

"I have to say, Chicago Police Department, everybody just responded very well and all the passengers were great," Sievers said.

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