"Infected" is a song written by Mr. Brett from the punk rock group Bad Religion. It was released in 1994 and appears on their eighth proper studio album Stranger Than Fiction. Along with "21st Century (Digital Boy)", "Infected" is considered to be their breakthrough song, as it received airplay from modern rock radio stations.

This song was also released on Guitar Hero for the Playstation 2 and later as a part of a 3-song pack via Xbox Live for the Xbox 360 title Guitar Hero II on April 11, 2007.

More than a decade after its release, "Infected" also remains a concert staple.