I was on an airline flight last night that had a first class passenger two rows in front of me get violently sick and go into the first class bathroom. His bodily liquids were flowing from underneath the door and down into first class!
The flight attendants were great in that they were quick to prevent further spread of his fluids by throwing down lots and lots of blankets. They asked for a doctor. A guy came from the back and started attending to him. They blocked visual access to the front galley/lav area by hanging blankets. They cleaned him up. Cleaned the floor. Took him back to coach where there were a couple of rows of empty seats and laid him down there. After landing, medical personnel responded and removed him from the plane first. He was visibly ill; most likely food poisoning.
I had two bottles of Purell with me and they were nearly empty by the time I left the airplane!!