In September 2005, shortly after the introduction of Zul'Gurub to World of Warcraft, a virtual plaque broke out. Players who defeated the last boss Hakkar, contracted and then spread a disease called, "Corrupted Blood," throughtout the fictional world of Azeroth. Scientists are now claiming that this is an example of how virtual worlds could be used to study human behaviour during epidemics.
The, "Corrupted Blood," disease was contracted upon killing the last boss in Zul'Gurub. Players and player pets close to the corpse of the dead boss would contract the disease. A bug in the programming led to the pets spreading the disease to computer controlled characters and player controlled characters alike. Due to the fact that the disease had been designed to challenge high level players, many low level players died instantly upon contracting the virtual illness from fellow players and computer characters. Forum and fan site members world wide began to report hundreds of dead bodies lining the streets of cities and towns in the virtual world. Some people purposely spread the disease whilst others tried to flee the mayhem being caused by the accidental virus outbreak.
Human behaviour has a big impact on disease spread. And virtual worlds offer an excellent platform for studying human behaviour.
The players seemed to really feel they were at risk and took the threat of infection seriously, even though it was only a game.
Blizzard countered the outbreak of the disease by performing rolling restarts of effected servers and applied quick fixes to resolve the issue but many players said that the problem continued well after these rolling restarts and fixes were completed.
Scientists claim that this method of study would be pheasable as it would be unethical to release a real virus into a population simply to observe how people reacted.
Despite this theory, other scientists have highlighted problems when studying human behaviour in fictional and none-fatal situations, questioning how reprisentative of real life virtual worlds really are.
Although the characteristics of the disease could be defined before hand, once released into the virtual world, the study is just as 'observational' as disease outbreak studies in the real world.
Despite this, scientists have said that this would provide them with a platform to make observations that would otherwise not be possible.