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What Plague Inc. Teaches Us About Ebola and Pandemics

Plague Inc PC

“Damn you, Madagascar!”

If you’ve ever played Plague Inc., or its inspiration, Pandemic 2, then you’ve no doubt cursed Madagascar or Greenland for being so difficult to infect. In these games, you take on the role of an evolving disease with a singular goal: the complete annihilation of the human race. You infect, you spread, you mutate, you kill.

Mixing elements of strategy and simulation, Plague Inc. became popular enough to attract the attention of the Centers for Disease Control and Prevention (CDC) – the United States’ public health institute. In March 2013, creator James Vaughan was invited to the CDC to talk about his game, where he was lauded for raising public awareness “on epidemiology, disease transmission, and diseases/pandemic information.”

Is the Plague Inc. dev worried about a global Ebola pandemic?

With the recent Ebola outbreak raising concerns about the possibility of a global pandemic, it turns out that Plague Inc. goes a long way to laying such concerns to rest. We caught up with James Vaughan to get his opinion. “The current Ebola outbreak is horrific and deeply concerning,” Vaughan told The Escapist, “but unless things change significantly, I don’t believe we are looking at a full Plague Inc. style situation here.”

Vaughan pointed out two reasons why he isn’t concerned about the outbreak becoming a global pandemic. First, Ebola has no carrier state. “If you are infected, it is very obvious,” said Vaughan. “It is not possible to have infected but asymptomatic people spreading the disease.” HIV, for instance, has a long period during which a carrier shows no symptoms of the disease, which has helped its propagation. The historically famous case of Mary Mallon – aka Typhoid Mary – is a classic example of an asymptomatic carrier who infected dozens of people without ever becoming “sick” herself. Asymptomatic carriers allow a disease to spread before measures could be taken to quarantine the carrier – it’s a sneak attack.

The latest estimates I saw suggested it would take two to six months [to bring the outbreak under control].

The second reason Vaughan points to is the fact that Ebola is not an airborne disease. Because it relies primarily on fluid contact to propagate, it is “much easier to prevent the spread of Ebola by adopting the correct precautions and processes.” Since quarantine is the best measure to preventing the spread of Ebola, the ability to so clearly identify infected individuals allows for no surprises. Don’t touch an infected person – it’s that simple.

Vaughan explained that the location of the outbreak has resulted in significant cultural and logistical challenges to overcome. For instance, raids on hospitals due to public disbelief in the government’s Ebola claims have resulted in quarantine being broken, and the lack of a first-world infrastructure and facilities means some regions have neither the means nor the education to maintain proper sanitation standards. Still, he believes the outbreak can be brought under control. “The latest estimates I saw suggested it would take two to six months,” he said.

Simulating Ebola in Plague Inc.

Two to six months – that would make the duration of the outbreak, as a whole, roughly one year. I decided to boot up Plague Inc. and try to simulate the situation in order to see how the game would resolve the outbreak. After choosing West Africa as my starting region, I did my best to evolve traits that matched Ebola: transmission through blood, symptoms including vomiting, diarrhoea, rash, haemophilia, internal haemorrhaging, and total organ failure, as well as numerous abilities to delay the production of a cure.

…very few laboratories in the world can work with the live [Ebola] virus.

According to David Wang, PhD candidate in biochemistry at Canada’s McGill University, we’d be years away from an Ebola vaccine, even with first world nations making it a priority. Part of the problem is that Ebola is BSL-4 virus, “so very few laboratories in the world can work with the live virus,” he told The Escapist. BSL-4 – or biosafety level 4 – invokes the highest levels of containment for biological agents. Further, “We will need a much greater understanding of Ebola’s molecular mechanism,” he explained, beyond merely how it presents symptoms. Even if expediting measures would be taken – such as skipping several drug trials – Wang estimates a vaccine would be at least one year away, and likely even two to three years away.

Within two months, my simulated Ebola had infected 57 people in West Africa. By contrast, according to the World Health Organization, 49 cases of Ebola were estimated by March 22, roughly three and a half months after the initial outbreak. While we can argue that the sim was fairly accurate so far, the main disparity was the fact that Ebola had already killed 29 people by that point, whereas my sim’s death count remained at 0. Today, roughly nine months after the initial outbreak, 2,615 cases of Ebola have been reported, as well as 1,427 deaths caused by the virus. In my sim, it took three and a half months to reach 2,828 infected, with 0 dead. In fact, it took four months and almost 700,000 infected people before the first deaths began to appear, and five months for the world to detect the existence of the disease.

Thereafter, the numbers grew out of control, and any semblance of simulation was lost. After six months, over 300,000,000 living people were infected and over 8,000,000 were dead – at that point, West Africa shut down its land borders. Curiously, the timeline for how long it took West African nations to close their borders in real life roughly matches. 11 months in, death counts were approaching 800,000,000, a number of countries were infected, and West Africa had fallen into anarchy. After roughly two and a half years, the outbreak finally died out, after killing roughly 4.7 billion people.

What can we learn from the sim?

Plague Inc icon

So what went wrong? Why was my simulated Ebola so inaccurate? Part of the reason was that it took me a long time to evolve all of Ebola’s deadly symptoms, which was reflected in it taking a long time for the disease to start killing people. But the other reason is that Plague Inc. simply isn’t designed for a disease like Ebola. “The default Plague Inc. models rely on the potential for asymptomatic carriers as well as airborne transmission,” said Vaughan, “preventing perfect modelling of Ebola.” Basically, my simulated Ebola was spreading more than its real-world counterpart. Of course, this is by design – after all, regardless of how accurate it may be, Plague Inc. is a game and not a true simulator. “The algorithms in Plague Inc. are very complex and do a good job of modelling the world – however, it is important to note that Plague Inc. is a game, and I have had to depart from realism in places in order to ensure it is fun,” said Vaughan.

But that doesn’t mean my exercise was one in futility – on the contrary. In fact, any adept Plague Inc. player can testify that a winning strategy is to keep your lethality and visibility low and your infectivity high until you’ve spread throughout the world. With Ebola, both real and simulated, the fact that its lethality and visibility is high – that is to say, it kills its host fairly quickly and it presents very visible symptoms – means that it will likely never be a world-killer. My Ebola died out because it simply couldn’t spread fast enough, relative to how fast its hosts were dying and how quickly countries were closing their borders. Similarly, real-world Ebola is too visible and too effective a killer to pose a threat to humanity’s existence.

Will an Ebola scenario be added to Plague Inc.?

Plague Inc. includes scenarios for swine flu, smallpox, zombies, and most recently, through a partnership with 20th Century Fox and Dawn of the Planet of the Apes, the “Simian Flu.” Vaughan has received many requests to add an Ebola scenario to his game to more accurately simulate the current outbreak; however, there are no current plans to do so. “It is very important not to appear to be trivializing such a serious issue,” he said, and I can only imagine the number of people who would accuse him of trying to cash in on tragedy were he to release an Ebola scenario. Instead, Vaughan has been in talks with a few charities and organizations involved in combating Ebola about using Plague Inc. to raise either awareness or funds for the cause.

Plague Inc CDC

While there is still work to be done to stop the outbreak, Vaughan feels we’re in safe hands. As part of his visit to the CDC, he was also given a tour of the Emergency Operations Center, which is where the CDC is currently managing its response to the Ebola outbreak. “I find it reassuring to know that there are so many dedicated people working to keep us all safe,” he said. Vaughan called his trip to the CDC “exceptionally interesting,” and from it was able to draw a huge amount of background material for modelling the human response to pandemics. The trip has helped shape the development of Plague Inc.: variables relating to how different countries react to pandemics were tweaked, real-world CDC news headlines were added to the game, and the most obvious thing to players is that the CDC will attempt to locate Patient Zero – the first person to have contracted the disease.

It may not be the perfect pandemic sim, but Plague Inc. has likely done more to educate the public on disease transmission than many awareness campaigns. “I think Plague Inc. is best at communicating the broad threat of a pandemic as well as highlighting specific elements of Ebola and other infectious diseases,” Vaughan says. “Most importantly, I think it shows players how a disease in one country can threaten the whole world.”

The threat of global pandemic is out there – it’s just not Ebola. It’s the quiet ones you have to look out for.


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