Plagues are a calamity that seem to happen very often in World of Warcraft, or at least more often than they do in most other games.
These plagues, which exist outside of the game's storyline and aren't actually a part of any planned events Blizzard has for its players, are emergent scenarios that crop up from time to time as unintended consequences of certain game mechanics.
The previous pandemic, or at least the last big incident covered by the gaming media at large, ocurred in 2005 with the introduction of a boss in the Zul'Gurub dungeon named Hakkar would cast upon players a slow working hit-point draining and highly-contagious debuff called "Corrupted Blood."
The incident was named after the spell itself, and while intended only to last for a few seconds and function only within the dungeon spread across the entirety of Azeroth when players discovered that they could teleport out of the dungeon and infect others with it. The spell quickly spread from player to player within the game's cities and no amount of developer-mandated quarantines or abandonment of these locations could stop the disease from spreading. The developer finally able to stop the disease by patching it out and resetting all the servers.
The Corrupted Blood incident served as a study for real-world security experts and epidemiologists as a model for disease vectors and bioterrorism.
Yesterday, a newly uncovered bug allowed players on Death Knight characters to cast plagues on friendly targets sparking an epidemic of much more modest proportions. Unlike the Corrupted Blood incident, which spread contagiously from player to player unhindered, the new bug had to be cast willingly and upon a single target. It has since been fixed.
That said, the new plague wasn't without its high deathtoll as Death Knights rampaged throughout the lands, killing everyone in their path.
Thanks Polygon.
