World of Warcraft Epidemiology - The Corrupted Blood Plague (And Why It Matters) - Extra Credits

Welcome one and all to a nice fireside tale of death and epidemics. Now, since we've been covering a lot of real-life plagues on Extra History, we figured we'd cover a virtual one here. One that shook the largest game in the world to its core, and in the process, provided scientists with data that may help save actual lives in the future. Thanks so much to Squarespace for sponsoring this episode. Click the link in the description below to see just how perfect Squarespace is for your next online idea. Now, let's turn this way-back machine all the way back to September 13th, 2005. Far to the south, far from the halls of Stormwind or the furnaces of Ironforge, a group of adventurers find an ancient ruin deep in the jungles of Stranglethorn. It is a forgotten troll city, but one powerful troll priest has,

in secret, been using it as a ritual site to bring a dark god back from beyond. The adventurers fight their way through the abominations and overcome horrible traps to at last face this ancient evil. With a mighty cry, they engage the malignant deity. With their magics learned from a lifetime of study and their weapons scoured from the deepest delves, they strike at it. But one by one, they start to sicken. There is a corruption this god has brought into the world. But these are true heroes, champions of Azeroth. They battle through the sickness and at last overcome the ancient evil hiding in the jungle temple grounds. Their clerics, great healers all, cure the wretched contagion that has seized so many of their band. And world saved, they set out for home. But no one remembered to cure the hunter's pet. As is true so often in real life, the

pet was the carrier. When high-level groups raiding Zul'Gurub would return to use the bank or sell their loot in major cities, the pets and minions they brought with them would carry the disease, and vast outbreaks would occur. The disease was called corrupted blood, and it was intended only to affect groups within Zul'Gurub, one of the hardest zones at the time, meaning that it packed quite a punch. Not enough to kill off level-capped raid players, mind you, but certainly enough to obliterate low-level characters. Luckily, that wasn't something anyone at Blizzard had ever had to worry about because it was supposed to be contained to only an end-game zone. But due to the bug that let the pets carry it out of the zone, the moment the high-level players returned to the cities that plenty of low-level players passed through, it just decimated the population. Both Horde and Alliance capitals, Stormwind and Orgrimmar, were filled with the unburied dead. Corpses and skeletons littered the streets. And then

people acted, well, like people, which is what makes this event so interesting. This is what made scientists study the outbreak because even though it was just a game, so much real-world behavior occurred. Players started to flee the cities, to abandon them for fear of the plague. In doing so, they brought the plague with them, moving along travel routes to smaller and smaller outposts. Quarantines were set up, but one by one, the quarantines were breached. Sometimes by sick players trying to get out of the perpetual cycle of dying and respawning in affected areas, sometimes by players transporting pets they were unaware had the plague. Altruistic players worked together to set up healing stations, or even just rush in to try to cure low-level players that had contracted the plague. But especially in the less organized of these efforts, healers rushing in to save new players would often accidentally contract the disease themselves, and became a vector for the

very disease they were trying to stave. Other players decided that, sick or not, they still needed to make money. So, they did the equivalent of going to work. They'd send their plagued character to the auction house to try to get some transactions done, and ended up spreading the disease to everyone around them. Worse still, NPCs in the game functioned as asymptomatic carriers. An NPC could contract the disease, but they had enough health they wouldn't die. And the disease had no visible effects, meaning there was no way to tell they had the disease. Just like in real life, where sometimes people carry a disease without it actually affecting them. And because these NPCs were asymptomatic carriers, it meant that when someone went to work sick and walked up to one of those auctioneers, they'd infect that auctioneer. And someone coming into the auction house after them might contract the plague from the auctioneer without even knowing the NPC had it.

There was also an organized effort to have people flag themselves as infected if they caught the plague, in order to help with quarantines and allow new players for whom the disease would be fatal to avoid them. This system broke down, too, though, because some players would intentionally try to infect anyone without the disease, which led uninfected players to start flagging themselves as infected so people wouldn't intentionally try to make them sick, rendering the whole system useless. In the end, Blizzard had to do a hard reset on the servers and roll out some new patches, because unlike a disease in real life, in WoW, players respond. Meaning the disease could essentially go on forever, which is one place where studying things like this breaks down. Interestingly, though, we get another real-world analog here. If you think of high-level players, players who could survive the plague, as healthy adults, and low-level players as vulnerable populations such as children or the elderly. If players couldn't respawn, the plague

was so deadly that it would have burnt itself out rather quickly, though leaving quite the body count behind. Which brings us to the last point. This event has been the subject of a number of academic papers. Why? Because pandemics are, thankfully, rare. But that means we don't have a lot of data on them, especially how humanity behaves during them. Virtual environments like World of Warcraft provide a unique opportunity for scientists and researchers to get insight into an absolutely vital area of study without the immense real-world toll. And virtual studies will be, by their nature, imperfect. And every scientist talking about this mentions how clearly they recognize this going on. But given how the Warcraft community seemed to treat it like a real plague, even though the stakes were seemingly so low, there's data to be gained, and that's an incredible thing. I'd love to see an MMO company team up with researchers for something like this, because the more we know, the less

lives the next big outbreak will take. And considering none of us get real-life respawns, that's a quest I'm willing to be a part of. Until next time. Once again, thanks so much to Squarespace for sponsoring this episode. Not only do they make it easy for our team at Extra Credits to share updates and have a clean and professional-looking website, but I've been using Squarespace for my personal online endeavors for years. And because I truly know nothing about web design, their awesome templates have helped my ideas look way cooler than they actually are for a while now. Plus, I can attest to their great 24/7 customer support, as well. A few years ago, I was going in for an interview, and I needed to embed a piece of content to my site. I had no idea how to do it, and once I contacted them, we figured it out in like 10 minutes. And with domain transfers, online storefronts, and their all-in-one platform, which looks slick no matter where you view your content, there's no better place to make your next online dream a reality than Squarespace.