According to Shacknews reader pigz [tip via EA], a new area boss in World of Warcraft is giving adventurers more than they bargained for. Characters fighting the boss are becoming infected with "Corrupted Blood," a contagion designed by the game's developers that is bothersome to high-level characters, but will outright kill low-level characters. According to pigz, the disease has been transmitted from players returning from the area of Zul'Gurub. It is then spread among the general population, including computer-controlled characters. "Some servers have gotten so bad that you can't go into the major cities without getting the plague," said pigz.

The virulence of the Corrupted Blood effect seems to have surprised Game Masters in charge of moderating the game play of World of Warcraft. According to pigz, GMs have quarrantined certain players, but have not been able to contain the outbreak.

This is the first case I am aware of where a video game virus created by the game's developers has proven to have such dangerous and sweeping in-game effects. In the virtual world of Second Life, users have worked to create their own diseases and virii.