Dawn of the Planet of the Apes opens onto a world where primates are at the top of the food chain, but not Homo sapiens. It takes place ten years after a lab’s race to develop a cure for Alzheimer’s disease resulted in genetically altered apes with heightened intelligence and a plague for the planet’s humans. The “Simian Flu,” as it was called, reduced humanity to a meager million.
Pandemics are always at our doorstep. In fact, all it would take to jump-start a real life Simian Flu is a favorable mutation to a virus burning its way through Africa as you read this.
In Dawn, the Simian Flu is a terrible disease. According to the fictional website set up for the film, symptoms begin 48 hours after exposure. After a few days of fever, headaches, and gastrointestinal distress, external and internal bleeding occurs. Death follows shortly thereafter.
The Simian Flu has a ghastly fatality rate of 90 percent—only one in ten who contract the virus survive. To stop its spread, doctors in Dawn‘s fictional timeline urge people to wash hands frequently, avoid publicly used surfaces, and to stay away from large gatherings of people. It’s decent enough advice that apparently wasn’t heeded. According to the film, the Flu quickly spread to millions. In these respects, Dawn perfectly reflects qualities of some of the worst viruses we’ve ever discovered.
In 1976, near the banks of the Ebola River in what is now the Democratic Republic of the Congo, we discovered a virus that would live on in popular culture because of its extreme ferocity and telltale symptomology. Dubbed the “Ebola Virus,” it was a viral hemorrhagic fever that affected human and non-human primates. Five strains have been discovered since 1976, four of which are known to infect humans.
Perhaps the writers of Dawn looked to Ebola viruses because of their mysterious nature. Outbreaks do occur, but they happen sporadically and swiftly. Ebola quickly burns through humans only to return to the deep African jungle. It doesn’t linger like influenza or AIDS. The writers were more likely interested in the morbid visuals that come along with an Ebolavirus infection—bleeding from the eyes, nose, and mouth. We can infer that the Simian Flu would be an Ebola-type virus because of how many symptoms the two pathogens share. Out of the 17 symptoms of Ebola listed by the Centers for Disease Control and Prevention (CDC), the Simian Flu shares 12 of them.
The fatality rates for Simian flu and Ebloa virus are also strikingly similar. Ebolaviruses have some of the highest fatality rates of any viruses we’ve encountered: up to 90 percent. They are killers second only to viruses like Smallpox and rabies, both of which have fatality rates of effectively 100 percent without treatment.
But one critical aspect that Ebolavirus species do not share with the fictional Simian Flu is the ability to become a pandemic. While there have been a number of recorded Ebola outbreaks in the last 40 years, each incident has left fewer than 600 casualties in its wake. Ebola is terrifying but occasional, and quickly self-extinguished. The better contender for the Simian Flu’s spread would be influenza—more specifically the 1918 pandemic dubbed the “Spanish Flu.” A variant of the milder influenza that comes around every year around fall (think H1N1 or H5N1), the Spanish Flu spread to 500 million people across the globe and killed 50 million, though official numbers are hard to determine. Three to five percent of the world’s human population at the time died fighting that virus.
Though the Ebola virus is a near-perfect representation of Dawn’s Simian Flu, it emerged in a much more natural way.
As David Quammen noted in his excellent book on emerging infectious diseases Spillover, “Everything comes from somewhere.” In the case of Ebolavirus and many other infectious diseases the place is other animals. Called zoonoses, viruses and bacteria can evolve to spill over from one species of organism into another. Some zoonotic viruses and bacteria don’t handle the transition well, and never fully make the leap. Others are successful but hardly affect the new organisms at all. Still others thrive inside the new hosts. Anthrax, cowpox, H1N1 flu, rabies, and Ebola are just a few.
Scientists aren’t positive what organism Ebola spilled over from, but the study is ongoing. Bats are likely culprits, passing on the virus directly to humans or indirectly through chimps and other apes into us. Eating the Ebola-laden “bushmeat” of chimpanzees has been cited enough times in Ebola outbreaks that calling the virus the “Simian Flu” isn’t that off-base.
In fact, if the Reston ebolavirus, a species of Ebolaviruses that causes hemorrhagic fever in non-human primates, made the evolutionary leap from primates to people, “Simian Flu” would be an almost perfect name.
Dawn of the Planet of the Apes picked a mysterious and terrible virus to base its Simian Flu on. The only way it differs from real-world Ebolaviruses is that it didn’t come from nature and that it has the ability to spread itself much further. That’s not to say the danger isn’t there. Scientists and infectious disease researchers keep a close eye on viruses like Ebola because of their potential for pandemic. Currently, Ebola is the serial killer of viruses. Ebola appears from time to time to kill a large number of people, but it never lingers and it doesn’t decimate populations. But it could. If the record Ebola outbreak that is burning its way through Africa right now mutated in just the right way, found its way onto a plane and into a densely populated city, there could be a Simian Flu-like event. We care about dangerous infectious diseases, even if they don’t affect the global population, because of evolution’s immense power. The AIDS pandemic is only the most recent example, but as human encroachment puts us into environments we’ve never been and into contact with organisms we’ve never seen, there will likely be more.
A perfectly evolved flu could certainly catch humanity off-guard. It has happened before. But we are learning more and more about how to stop pandemics before they start. Movies like Dawn are able to pick up on scary viruses exactly because we know much more about them now—how they infect us, how they spread, how to kill them—than we did when we recorded the first cases.
Science then, epidemiology and virology in particular, is the way out of a pandemic on the scale of the Simian Flu…unless a potential cure inadvertently wipes out most of humanity save for Gary Oldman and gives non-human primates extreme intelligence and human-like vocal chords.
Kyle Hill is the Chief Science Officer of the Nerdist enterprise. Follow the continued sci-pop geekery on Twitter @Sci_Phile.
If you want to learn more about emerging infectious diseases, check out the book Spillover by David Quammen.