Was ‘World of Warcraft’ Once Hit by a Virus That Was Subsequently Studied by Researchers?

As the COVID-19 (aka Coronavirus disease) continued to spread in March 2020, social media users flashed back to a “pandemic” that unfolded nearly 20 years earlier — but this one took place entirely in the virtual world.

According to the Hong Kong-based tech news site AbacusNews.com, more people on the Chinese platform Weibo have begun researching the Corrupted Blood online virus and players’ responses to the bug, which broke out inside the World of Warcraft game platform (known as WOW for short) in September 2005:

A Weibo hashtag related to the World of Warcraft epidemic has become one of the most-searched terms, reaching nearly 60 million views. And one Weibo influencer spotted a similarity between their origins: The Wuhan coronavirus and Corrupted Blood both started in animals.

“On the fundamental level, Corrupted Blood started with a hunter’s pet, namely an animal, before it transmitted to a person,” the Weibo user wrote.

On Twitter, author Rin Chupeco garnered attention by highlighting the incident in a very popular thread and adding, “Epidemiologists actually STUDIED this to see how ppl would react to an epidemic [in real life].”

The Warcraft outbreak was an unintended side-effect of an update to the game involving the character Hakkar the Soulflayer, introduced for players in the online multi-player game to take down to complete a raid. One of Hakkar’s attacks siphoned off players’ characters’ “blood,” weakening them to replenish his own strength. The game allowed for players to contaminate (or “corrupt”) their characters’ blood and thus poison Hakkar. But the tactic could also affect characters’ in-game pet.

Engineers for the game told PC Magazine in 2019 that the problem originated from a mistake by the design team; if a character’s pet was in play at the time they poisoned Hakkar using that maneuver, the corrupted blood effect — and damage to not only the pet but any other character — would linger even after completing that part of the game.

“Every time you’d summon that pet you’d reinfect yourself and all the players around you and it wouldn’t check if you were in a raid so you’d do it while you were in town and the entire town would get corrupted,” said Shane Dabiri, chief of staff for the game’s manufacturer Blizzard Entertainment. The effect was further spread by players who willfully “infected” their characters, and then deliberately took them to other virtual sites on the WOW platform.

“Even once we figured out what was going on it made it really, really hard to fix it,” Cash said:

Our choices were either to go through every pet in every server in every country in the entire world and check if it had corrupted blood and get rid of it, or get really hacky code in where every time you summoned a pet it would check and see if it had corrupted blood on it and get rid of it.

At the time, an estimated 6.5 million players used the game platform. As Reuters would report in 2009, the corrupted blood outbreak, which lasted around a month, affected 4 million of them. But the situation also prompted researchers to take note.

In a March 2007 article for the journal Epidemiology, physician Ran D. Balicer from the Ben-Gurion University of the Negev in Israel called the purposeful spread of corrupted blood by WOW players “the first virtual act of bio-warfare” and drew parallels between that outbreak online and the public spread of other diseases in the real world:

The role of an asymptomatic-yet-infective animal reservoir, for instance, is evident in avian influenza. Asymptomatic ducks had an important role in allowing this otherwise relatively lethal avian disease to become endemic in East Asia and spread to other parts of the world. Furthermore, attempts by game administrators to quarantine infected areas proved futile due to the ability of characters to rapidly teleport to distant lands. This is similar to the role of air travel in the rapid global spread of severe acute respiratory syndrome (ie, SARS).

That same year, in a paper for Lancet Infectious Diseases, Tufts University professor Nina Fefferman and co-author Eric Lofgren from the University of North Carolina argued that because WOW players can be so immersed in the game, that their reactions could be used as a gauge for how non-gamers could react in the event of a real-world outbreak:

The modern world has two distinct types of pathogens, real and virtual. Real pathogens are, logically, those that infect real organisms, many of which subsequently cause disease and become subject to the attentions of the medical and public-health professions. The second type of pathogen, the virtual virus, infects computers through software. The outbreak we have described marks the first time that a virtual virus has infected a virtual human being in a manner even remotely resembling an actual epidemiological event. As technology and biology become more heavily integrated in daily life, this small step towards the interaction of virtual viruses and human beings could become highly significant.

More than a decade later, those respective analyses continued to hold true; Eric Lofgren, who as of March 2020 was working as an infectious disease specialist at the Washington State University veterinary teaching hospital, told the Canadian Broadcast Company that implementing planned outbreaks within virtual settings could provide data for how to combat viral diseases outside of them.

“In the real world, we can observe people’s behaviour, but we don’t know everything about the rest of the universe. We don’t know perfectly if you’re sick or not,” he said. “In a game, we can, at least in theory, know all of those things. They’re programmatic; you can record them.”