The Corrupted Blood incident is a famous “global” event in WoW where a large number of players were affected by an unplanned in-game event and seemed to offer potentially interesting insights to researchers of epidemiology. On September 13, 2005, Blizzard, the creators of WoW, introduced a new dungeon instance into the game with a new boss associated with the dungeon. The new boss had a spell (Corrupted Blood) that acted like an infectious disease. Once a player was infected they could transmit the disease to other players and even NPCs if they were close enough. The spell damaged the “health” of the other characters over time. Blizzard had created the spell to be confined to the dungeon instance where it was introduced. But the unintended consequence of the spell is that it started to spread like a plague and eventually infected a large percentage of players in a number of servers. A number of researchers in the field of epidemiology noted the similarities between how people reacted to Corrupted Blood in WoW and how people react to epidemics in the real world. Thus, Balicer noted in one of the first papers on the subject, “a platform for studying the dissemination of infectious diseases, and as a testing ground for novel interventions to control emerging communicable diseases.”
Beyond the obvious similarities between real world epidemics and the contagious nature of Corrupted Blood, researchers noted a number of other similarities: the Corrupted Blood originated in a remote, uninhabited region in WoW. It was carried by travelers to larger regions and also by players who were actively fleeing the main centers of the plague, the hosts for the plague were both human and animal. In these respects some regarded that it had similarities to the Avian flu virus. The similarities, however, end here and we should examine the efficacy of using virtual worlds to study these phenomena in the historical context. Earlier work in the field of Social Simulation focused on simulating influence and the spread of outbreaks but in a purely simulation-based framework where human agents are substituted for artificial agents. Thus the main limitation of this approach was that certain assumptions that were made about human behavior like rationality or even bounded rationality were not borne out by psychological studies of human behavior.
The excitement of the research community sprung from the fact that these virtual environments represented spaces where one did not have to rely on virtual agents anymore and collect real data about human reactions to contagious diseases without any harm being done to humans.
On the other hand, the lack of liability on the part of the human beings is also a problem with respect to correct modeling of the phenomenon. The maximum penalty in WoW for contracting plagues is the death of the player’s character, which can be regenerated. The player would at most lose some of the virtual resources acquired, but in the real world, a person who loses her life has no hope of ever being resurrected. People are likely to behave very differently when their lives are at stake. In conclusion, while there are a number of similarities between the two environments and the Mapping Principle seems to work well at first glance but the most important aspects of the two environments do not map and thus preclude us from making many useful conclusions about the real world in this case.