“My fellow scientists, I bring you astounding news. I have discovered an intelligent species on another planet. In form they are little more than a network of pipes filled with fluid. But these Pipeworks have created a rudimentary civilization, complete with art and scholarship. More remarkable still is their ecology. Though they interact with various other species including prey, pests, commensals, decomposers, and so on, those can largely be ignored as superfluous details. The overarching narrative of Pipework history is one of an ongoing battle with a single other life form. This second creature is smaller, less brainy but more elusive, resembling a rounded pellet. The Pellets and Pipeworks have been at war for tens of thousands of years. Pipeworks have been slaughtered by Pellets in such monstrous numbers that death by any other cause, including murder by other Pipeworks, pales in comparison. The Pipeworks have both invented and evolved striking tactics for evading the Pellets, but always with mixed success. The conflict touches all. The great stories of Pipework history. The fates of their societies. The Pipework nations that have prospered while others have crumbled. Everything has depended on when and where Pellet sieges have been the most devastating. To this day, despite all of their technological advances, the Pipeworks have been unable to win the war, and hundreds of millions of them suffer Pellet attacks. However, for the first time in Pipework existence, victory seems to be within their grasp. If they unite as a species and face their ancient enemy, they may succeed in driving the Pellets to extinction. If they do, it will surely be their single greatest achievement, a vindication of all of their struggles. Simultaneously, it will be a bittersweet loss of their steadfast partner in the coevolutionary dance. Regardless, it will usher in an era of relief and resolution that will define them from that point onward.
“Following protocol, I also provide the relevant terms in the local dialect. The Pipeworks refer to themselves as Humans, the Pellets are called Plasmodium, and affliction with Pellets is a condition known as Malaria.”
Well, my fellow Pipeworks. Sit with that a bit. Only an extraterrestrial researcher (if they existed) would distill human existence down to such a simple story. But it’s a plausible perspective. If you had an intergalactic-eye view, you could easily take away this lesson. That malaria has always been our dominant foe and kingmaker, far overshadowing any others. The odd thing is that we hardly ever tell our own history this way. Plasmodium plays a minor role at best in our textbooks, ballads, myths, and movies. We convince ourselves that we are noble, and having a piddling protozoan as our chief nemesis is beneath us. But consider the facts.
First, what exactly is a Pellet? Plasmodium is a single-celled parasite. It’s distantly related to kelp. Its seaweed origins are revealed by an vestigial algae that still lives within it, which itself contains the remains of a bacterium that once could harvest light for energy like a plant. No longer. Instead, today the parasite gets its dinner by infiltrating the red blood cells of mammals, birds, or reptiles. It eats hemoglobin, the crimson protein that brings oxygen from our lungs. A malaria infection is basically a bacterial cell inside an algal cell inside a Plasmodium cell inside a human cell. It’s like a tiny turducken that kills people. When a thirsty mosquito sips a Bloody Malaria from your veins, the parasites get slurped up, too. Inside the insect they have sex and sire a new crop of parasites headed for another vertebrate. In humans, infection causes an excruciating, feverish, and often fatal disease. Most deaths are due to Plasmodium falciparum, named after the scythe-like falx, a weapon reflective of both the parasite’s crescent shape and its barbaric lifestyle.
As the alien ecologist said, malaria kills a lot of us. An oft-quoted estimate is that has been responsible for half of all human deaths. This is such a rough guess, it’s hard to assess its accuracy. But it’s not unrealistic. And no other cause of death could reasonably come close. This year, around 3% of the world’s population will be infected with malaria, and 1 in 10,000 humans will die from it. Mostly children.
The mark that malaria has left on our genomes has no parallel. Sickle-cell hemoglobin, which evolved to convey resistance to malaria, is famously the most prominent example of adaptive diversity in our species. Other genes also coevolved with Plasmodium, such as the Duffy antigen, G6PD, and perhaps even the well known ABO blood types. These all show some of the strongest signatures of natural selection ever seen in humans. Because of these genes, humans vary enormously in our natural resistance to malaria. The difference is literally one of life and death. But, as is so often the case, we hosts have not been able to evolve a permanent barrier to infection. Plasmodium still finds ways to get in.
History is written by the vectors, as it were. The myriad ways that Plasmodium has shaped the human story could fill many books. And it has. I highly recommend Sonia Shah’s The Fever. Charles Mann’s 1493 also covers the topic thoroughly. To take just one particular aspect of our society, why are white people generally better off today, on average, than blacks? The reasons are complex, but, ecological factors, including parasites, have played a large role every step of the way. Within Africa, Plasmodium falciparum has driven cultural development ever since it first arose. The parasite helped Sub-Saharan peoples who were relatively resistant, like the Bantu, to conquer or displace more susceptible tribes. But no nation can maintain complete resistance, and in any case resistance caries costs like sickle-cell anemia. Picture a society suffering from bedridden laborers and scores of dying children. It would face quite the uphill slog to develop powerful governments and advanced technologies. Eurasia, meanwhile, harbored a less deadly species of Plasmodium. Its peoples never acquired such strong immunity. Over the centuries, the flow of ideas into Africa was probably hampered. Any northerner who dared to venture to the tropics faced a Plasmodium falciparum death sentence. Later, when Europeans colonized the New World, Plasmodium took hold for the first time in southeastern North America. It killed both Native Americans and European colonists in huge numbers, prompting the desire for less susceptible African slaves. Europeans found it easy to dehumanize Africans, in part owing to the primal dread of the eldritch “dark continent.” Thanks to malaria, even temporarily docking a ship on the African coast posed a horrifyingly mysterious and lethal risk to white sailors. Meanwhile, the colder northern colonies prospered with few slaves or parasites. Later, during the civil war, malaria caused widespread illness and death of troops. It likely affected the duration and outcome of the war, and thus the context for emancipation. Malaria continued to fester in the South until the 20th century, primarily affecting the poor. So, the demand for the slave trade, it’s justification, and its aftermath were all intricately linked with malaria. If the parasite had never existed, the world might look a lot different.
In fact, malaria’s signature is never far from anything you touch. Why do we drink gin with tonic water? Malaria. Why is the Center for Disease Control based in Atlanta? Malaria. Why is Scotland united with England instead of being an independent colonial power? Malaria.
And why can’t we get rid of it? One word: evolution. Our immune systems keep finding ways to prevent infection. Plasmodium evolves a new way in. We kill mosquitoes with insecticides. The suckers evolve resistance. We develop anti-malarial drugs. The parasites evolve around them. We develop molecular tests to detect Pellets in blood. They evolve to hide in plain sight.
This is not to say that eradication is impossible. Indeed, for the first time in history, we could well see the extinction of malaria in our lifetimes. But it won’t be easy. Outmaneuvering a wily Pellet requires a multi-pronged approach. A single pill or vaccine, administered haphazardly, is a sitting duck for evolution. And any kind of dedicated and comprehensive strategy to prevent counter-resistance has to be organized. It will take stable institutions and agencies right in the middle of the poorest and most volatile parts of the world. We need as many social safety nets as bed nets.
So, on the one hand I applaud the efforts of anti-malaria charities who drum up support for this herculean effort. On the other hand, all the rah-rah ambition can oversimplify things, just like the alien ecologist does. It’s not enough to just send medicines or bug sprays to the Third World. The people who live alongside Plasmodium don’t see it as Public Enemy Number 1. To them it’s just one of many hardships in life. As entrenched and as difficult to evict as the common cold. There’s wisdom in that. They know that not everyone in their community will enact a preventative procedure as they are told. After all, do all Americans remember to eat plenty of fiber and exercise daily? And we’re not being lectured at by a foreign colonial power with a history of dubious motives. In the past, overconfident efforts have just made things worse. Plasmodium merely evolves resistance to a drug and renders it useless.
I believe that fighting malaria is one of the most important and beneficial causes we can pursue. But we have to do it right. Perhaps it helps to think of Plasmodium as our equally-matched primary foe. So we don’t forget to respect it. So we take it seriously. If you have lived a life free of malaria, take a moment to appreciate that and don’t take it for granted. Your life is hardly the norm. For millennia, Pellets have never run out of tricks. But let’s see how smart we Pipeworks can be.