|Yeah, that's the one.|
About a year after it was launched, developer Blizzard Entertainment added a new dungeon raid to the game. The boss of this dungeon used a debuff power called "Corrupted Blood," which dealt significant damage over a short amount of time and could pass from player to player. For high-level players in the dungeon it was a mere annoyance, but if it were to hit a low-level player, they would almost certainly die. That shouldn't have been a problem, as the dungeon was intended for high-level players.
However, Blizzard failed to account for teleportation. It only took one or two players teleporting out of the dungeon for the debuff to spread like a disease. Someone ended up in Ironforge, a major city, while they were affected. From there, all hell broke loose. Corrupted Blood infected the entire city before long, and anyone leaving in a hurry simply brought it with them. Within days, the entire server was brought to its knees. Ironforge was almost literally paved with the bones of fallen players.
|Games are fun!|
It was an all-out plague. Some players volunteered to help direct traffic away from hot zones. Some were more hands-on: healers offering their abilities to the stricken. Some treated the whole thing like what it technically was: a game. They intentionally contracted the disease and then charged headlong into healthy clusters of people. Word got out to the real world, and the behavior of players in the game piqued the interests of epidemiologists and, since the more cavalier players were treating the disease like a biological weapon, counter-terrorism experts.
|Blizzard dropped the ball when they failed to implement this armor|
After quarantines, public bulletins, and tightened security failed to stem the tide of the Corrupted Blood Plague, Blizzard decided that it was time for a hard reboot. They were unwilling to risk losing subscription revenue over what was, in hindsight, a pretty bitching role-playing opportunity, so they shut down the server and removed the debuff.
|The time-honored Etch A Sketch Solution|
There have been a few similar incidents since then. Some were intentional, some were similarly caused by glitches and exploits. None of them were on quite the same scale. Today, prominent minds in the field of epidemic research believe that something similar to the Corrupted Blood incident could solve the major problems of their study models.
That's right. A video game, and a notorious one to boot, could be partially responsible for saving the world from a plague one day.