Cities like the dwarven town Ironforge and wow gold classic orc town Orgrimmar were overrun within hours. Non-playable characters, who couldn't die due to particular coding, could also catch the effect, meaning any participant who passed by them could get Corrupted Blood.

Once word got out, players hunted frantically for information about what was happening.

"The world chat would burst any time a town fell," says Nadia Heller, an ex-World of Warcraft player whose character lived through the incident. "We kept a close eye not just on our guild conversation but on earth chat as well to determine where not to go. We didn't want to catch it."

The spread of Corrupted Blood, and the player's behavioral modifications to it, caught the attention of epidemiologist Dr. Nina Fefferman, that had been a World of Warcraft player at the time of this incident. Fefferman reached out to her colleague Dr. Eric Lofgren. In 2007, the two published a paper that detailed their findings, including complicated models of individual behavior in a pandemic. Fefferman claims the incident has helped inform her current research to predictive modeling about covid-19.

"What I really do is research all the elements of infectious disease outbreaks which help us prepare for pandemics," explained Fefferman, a mathematical biologist. "We saw the complete variety of behaviors we see in the actual world reflected from the player characters during Corrupted Blood."

Dr. Dmitri Williams, an associate professor in USC who was also playing buy wow classic gold through the Corrupted Blood episode, questions whether Fefferman's findings are legitimate mirrors to real-life behavior.