World of Warcraft Could Have Helped Fight COVID-19
On September 13, 2005, World of Warcraft, the immensely popular MMORPG, rolled out a challenging new dungeon raid designed to push high-level players to their limits. This 20-player mission culminated in an epic showdown against Hakkar the Soulflayer, an ancient and malevolent blood god. Among Hakkar’s arsenal was a sinister ability known as Corrupted Blood—a debuff that struck victims with an initial burst of damage, followed by additional harm every two seconds for ten seconds total. What made Corrupted Blood especially dangerous, however, wasn’t just its damage—it was contagious. The effect could spread like a virus to nearby players if they were within a certain distance while it was active.
Due to an unforeseen programming flaw, the infection didn’t stay confined to the dungeon. Instead, it escaped into the wider game world and over the next month, entire regions would become decimated as millions of skeletons blanketed the land as millions of characters succumbed to the invisible plague. This virtual pandemic, now famously remembered as The Corrupted Blood Incident, turned a simple game mechanic into an unintentional, real-time simulation of an uncontrollable outbreak.
There Will Be Blood
Corrupted Blood was originally designed to function solely within the confines of the raid dungeon. Players afflicted by it would automatically be cured upon leaving the area—a safeguard that worked, but only for player-controlled characters. What the game developers hadn’t anticipated was that non-player characters (NPCs), particularly pets and companions, could also carry the infection beyond the dungeon’s walls.
Much like zoonotic diseases in the real world—viruses that originate in animals and jump to humans—Corrupted Blood found an unexpected vector. In World of Warcraft, certain classes can summon and control combat pets. These pets, classified as NPCs, were vulnerable to the infection during the battle with Hakkar. But unlike their human counterparts, they didn’t shed the disease upon leaving the dungeon. Infected pets could be dismissed mid-fight and later re-summoned in any location, still harboring the virus. This loophole allowed players to unknowingly unleash the plague in densely populated cities, turning bustling hubs into wastelands filled with player corpses.
In towns where the infection hadn’t yet spread, rumors of it did. In 2005, social media was still in its infancy, word of the outbreak traveled quickly through forums, chat channels, and word of mouth. Curious and skeptical players logged in just to witness the carnage firsthand, often becoming accidental carriers themselves.
Now it’s important to understand that Hakkar the Soulflayer wasn’t just any enemy—he was a top-tier boss found in a high-level dungeon, and his Corrupted Blood debuff reflected that level of difficulty. So much so, that the infection’s potency was devastating to low-level players, often killing them instantly from the initial damage, while mid- to high-level characters succumbed to the lingering effects of the damage-over-time component. In many cases, players were dead before they even realized they’d been infected.
From a typical gaming perspective—and conventional wisdom, it would’ve seemed logical to assume the outbreak would quickly resolve itself. Once the infected players had all died off, the disease should have had nowhere else to spread, at which point would simply respawn with healthy characters, the game world could stabilize, and virtual life would return to normal.
However, the NPC problem had unknowingly gotten even worse. Not only could NPC’s become infected, but NPC’s can’t die, and because they have no health stats, they showed no outward signs of infection, meaning that thousands of NPC’s around the world became asymptomatic carriers of the disease. So, when players spawned back in, the cycle began anew.
First Responders
Frustrated with a lack of communication from Blizzard, the game’s developer, hundreds of dedicated players decided to take matters into the own hands. In a remarkable display of self-organization, they began establishing makeshift quarantines around major cities and populated zones in an attempt to slow the outbreak’s relentless spread.
High-level players who could endure the effects of Corrupted Blood took on the role of investigators, venturing into contaminated urban areas to assess the damage and gather information. Meanwhile, lower-level players—too vulnerable to survive even brief exposure—stationed themselves at the outskirts of infected zones, acting as lookouts and issuing warnings to others approaching the danger.
In addition, Support-focused players, particularly those with healing abilities, volunteered as frontline medics. Working in shifts, they attempted to stabilize infected players long enough for the debuff to wear off. But in another sobering parallel to real-world epidemics, these digital first responders often became victims themselves—infected while trying to save others.
Perhaps the most striking aspect of this virtual crisis response was that none of it was mandated by the game. No system or quest told players to form quarantine lines or heal the sick—they did it entirely of their own volition. By the time Blizzard issued an official statement advising players to self-quarantine while they worked on a solution, they had already done so.
Bioterrorism
Blizzard’s initial efforts to eliminate the Corrupted Blood outbreak met with limited success—undermined, in part, by a small but determined group of players who actively worked to sustain the chaos for their own entertainment. These digital saboteurs exploited the game’s mechanics, retreating to remote mountain regions to avoid detection and periodically reentering cities to reignite the infection. Some even jumped between servers to escape clean-up efforts, effectively evading Blizzard’s containment strategies and spreading the virus across realms.
This unexpected layer of human behavior caught the attention of experts beyond the gaming world. Charles Blair, Deputy Director of the Center for Terrorism and Intelligence Studies, remarked that World of Warcraft presented a novel and potentially powerful platform for studying how decentralized terrorist cells form and operate. While traditional research relies heavily on theoretical models, Blair noted that an environment like World of Warcraft—populated by real individuals making unscripted decisions in a complex, bounded system—offers a more dynamic and realistic simulation. For military intelligence and behavioral analysts, the game inadvertently became a living lab for observing the mechanics of disruption, resistance, and coordinated sabotage.
COVID-19
As the World Health Organization (WHO) began formulating its strategic response to the emerging COVID-19 pandemic, officials sought out models from past crises to guide their planning. However, the last truly global pandemic was the Spanish Flu of 1918, and needless to say, society is very different from what it was a hundred years ago. More recent outbreaks like SARS and avian influenza had been regionally contained, leaving uncertainty about how those response strategies and protocols would translate on a global scale. One of the only case studies available resembling a global-scale outbreak in the modern world was the Corrupted Blood Incident in World of Warcraft.
While the WHO would study everything Blizzard did in order to stop the spread of the disease, more importantly, they observed how the public responded to the warnings and how many players didn’t take them seriously. The WHO warned governments that people would not change their daily routines if they don’t think the situation is serious, a pattern that echoed in real-world populations during the early stages of COVID-19. The incident demonstrated a critical insight: merely issuing guidelines or restrictions is insufficient—they need to be enforced. Analysts repeatedly cited the World of Warcraft case when advising governments that public health messaging alone would not guarantee cooperation.
Across the medical and epidemiological communities, the Corrupted Blood Incident became an unexpectedly relevant and widely referenced example of outbreak dynamics. In fact, as early as 2005, the U.S. Centers for Disease Control and Prevention (CDC) reached out to Blizzard, hoping to study the event’s simulation data in order to help them prepare for a real-world situation.
Unfortunately, Blizzard refused, insisting that the outbreak was nothing more than a programming glitch and maintained the position that, “World of Warcraft is first and foremost a game, and was never designed to mirror reality or anything in the real world.”
