The Corrupted Blood Incident: What World of Warcraft Taught Us About Epidemics

It was 2005, and the world couldn't stop talking about World of Warcraft. In mid-September, Blizzard added a high-level zone ruled by Hakkar the Soulflayer, who had an infection called Corrupted Blood. The infection was supposed to stay contained, but a programming error turned it into a virtual pandemic, killing thousands of players in cities. The so-called "Corrupted Blood Incident" became so important that epidemiologists ended up studying its effects...

With the arrival of COVID-19, we have lockdowns, social distancing, economic crisis, hoarding, rebels defying quarantine, a good dose of panic, and uncertainty. However, most of these events are not exclusive to the real world. Video games have explored the concept of an epidemic more than once, but if there is an example that stands above the rest, it's the historical Corrupted Blood Incident that struck World of Warcraft between September 13 and October 8, 2005.

It all began with the introduction of a new raid called Zul'Gurub, designed especially for high-level players. At the end, Hakkar the Soulflayer, the Blood God of the Gurubashi trolls, awaited them. The difficulty was considerable, and some players chose a "strategic retreat" before falling to Hakkar... but there was a small detail: Hakkar has a spell, an extremely contagious debuff that passes from one player to another called Corrupted Blood. This spell damages players' health over time, but it is also supposed to be his Achilles' heel, because by taking blood from players to heal himself, Hakkar introduces the debuff into his own body, allowing players to destroy him.

So what exactly happened? Of all the players who retreated from the fight, some were Warlocks with their minions, and others were Hunters accompanied by their pets. Both minions and pets served as asymptomatic carriers for Corrupted Blood, which in theory should never have left the raid zone. And once the infected creatures reached the cities... all was chaos. Low-level players died almost immediately due to the power of Corrupted Blood. Panic was total. The main cities were abandoned to escape the infection. All quarantines failed.

38 days and thousands of virtual corpses later, Blizzard had no choice but to hit the reset button, implement a reboot and block the Corrupted Blood infection on minions and pets, limiting its scope to the raid zone as it should have been from the start. To this day, Blizzard insists it was a glitch, but its effects and player behavior automatically caught the attention of health specialists and epidemiologists around the world.

Two of them, Eric Lofgren and Professor Nina Fefferman from Tufts University, published a study in September 2007 in which they examine the full development of the "Corrupted Blood Incident" and evaluate its potential as a tool to optimize and refine real-life epidemiological models, since they have precise data on how players behaved during the pandemic.

For example, those who tried to help with healing spells only made things worse because they didn't remove the underlying infection. Other adventurers decided to explore the infected and abandoned zones, ending up as new victims. And there were no shortage of sociopathic players determined to spread the disease. Professor Fefferman explains that much of her work is based on the social construction of "risk perception", and that this would have been much more difficult without the discussions that World of Warcraft players held in real time during the pandemic.

In summary, World of Warcraft became a valuable tool for anticipating and understanding how people behave during an epidemic-pandemic. It's not just about a virus making people sick, but about how each individual responds and reacts, whether they obey authorities or not. However, Lofgren warns that Corrupted Blood was something unexpected, a true black swan. In contrast, the coronavirus is nothing unexpected, and it reminds us of two things: That nature is very good at making people sick, and that there will be other pandemics in the future.

Source: Ars Technica. Access the study: Click here.