Campercraft
"How'd you sleep, Sam?"
"Didn't sleep a durn bit."
"Neither did I. I was shivering all night. I got up an' put the spare blanket on, but it didn't do any good."
"Wonder if there was a chills-and-fever fog or something?"
"How'd you find it, Sappy?"
"All right."
"Didn't smell any fog?"
"Nope."
The next night it was even worse. Guy slept placidly, if noisily, but Sam and Yan tumbled about and shivered for hours. In the morning at dawn Sam sat up.