Episode 31 of "Supernatural"
s02e09 Croatoan
Title: Croatoan
Original Air Date: 12/07/2006
Plot Outline:
After Sam has a vision of Dean killing a young man who seems to be possessed by a demon, the two brothers head off to Oregon to search for answers. They come across a town infected by a deadly virus that drives a person to kill. Sam becomes infected by one of the locals and prepares for his deadly fate, but after nothing happens to him, Dean decides to come clean and reveal what John whispered to him before he died.