Mother Nature has already given us so many things to be terrified of in this world—flesh eating bacteria, tsunamis, Tan Mom, to name just a few. Tapeworms certainly deserve a place on the list too. Who among us did not become obsessed with the idea that we might have one slithering around inside our intestines when we learned of their existence in science class? Well, it turns out having one in your digestive tract is the least of your worries, because according to one doctor who specializes in these kinds of things, there's actually an epidemic of tapeworms living in people's brains, wreaking all kinds of havoc. It's estimated that many millions of people are suffering from this affliction, and yet most of us have never even heard of it. If you thought getting a mind-controlling parasite from your cat was bad, think again.
This terrifying information comes courtesy of Dr. Theordore Nash, the chief of the Gastrointestinal Parasites Section at the National Institutes of Health. (Fun job!) He talked to Discover about this horrifying problem. Before we get to the shocking numbers, let's consider how this actually happens. How does a tapeworm work its way into your brain when it's supposed to be down in your abdomen, stealing all your nutrients and causing you to make jokes about your constant hunger like "Maybe I have a tapeworm!" until you find out you actually do have a tapeworm, at which point I imagine you start screaming and never stop?
Well, it's as simple as the worm taking a wrong turn. You see, normally tapeworms travel between pigs and humans during the course of their disgusting little lives. Tapeworms living inside people make eggs, which the unlucky person then shits out. Pigs eat this shit and swallow the eggs, and then the larvae hatch inside them and eventually make their way into the pig's muscles. There they wait until some unfortunate person eats that muscle, aka pork. If the pork is undercooked, then the consumer finds themselves with a nice case of tapeworms. Circle of life, etc.
But if the egg-infested feces accidentally contaminates a piece of food bound for a human's mouth instead of a pig's, which you can imagine happens quite easily, especially where food safety is not of paramount concern, then they hatch and burrow their way into our bloodstreams and often end up in our brains. Once there, they form cysts and pretty much stay as long as they like, destroying our brains in the process. It would be fascinating if it weren't so panic-inducing.
When a person ends up with tapeworm in the brain, the resulting cysts can grow and press on pretty much any area, which can lead to an array of horrible symptoms. Neurocysticercosis, as this disease is called, can also block the flow of cerebrospinal fluid, which puts pressure on the brain and can cause a coma or even death. The parasite can also cause seizures and violent convulsions of your muscles. But what's perhaps even more frightening is that they can sit in your brain for their entire lives totally unnoticed. Then, when they die your immune system finally picks up on them and begins to attack. This can cause damage to the surrounding brain tissue and dangerous swelling. What's more: this cycle of inflammation can continue for years, basically leaving you with never-ending problems. According to Nash, these patients used to just die, because there was nothing doctors could do for them, but now there are several treatment options, which while not perfect, can at least keep people alive.
As for these unlucky tapeworm-carrying people, just how many of them are there? Oh, millions. Nash says he estimates there are only 1,500 or 2,000 cases in the United States, but in developing countries the numbers are far, far higher. It's complicated to determine how many people have it, since public health systems in poor areas tend to be so, well, poor. But Nash says, "Minimally there are 5 million cases of epilepsy from neurocysticercosis." Though that number is probably a huge underestimate because the symptoms can easily be mistaken for other brain disorders. You really need a brain scan and blood tests to confirm a diagnosis, and this isn't usually done in the areas where the disease is most common. But Nash and some colleagues set about traveling in Latin America giving scans and doing the tests, and they found in Peru, for instance, that 37 percent of the people they tested showed signs of being infected at some point. Ahhhh! They've also done a review of scientific literature and figured out that there are likely between 11 million and 29 million people in Latin America alone who have neurocysticercosis. That is insane.
To give you a sense of scale, somewhere around 34 million people worldwide have HIV/AIDS, and we are rightly freaking out about that. If you extend the tapeworm numbers from Latin America worldwide, we're looking at a truly massive number of people. Or, as Nash calmly puts it, "Neurocysticercosis is a very important disease worldwide." And yet for some reason most of us have never even heard of it. Sure, we're probably glad that we haven't been aware of it until now, since it would have been all we ever thought about. (Sorry for ruining the rest of your life!) But our ignorance on the matter is costing many people their health.
Finding a cure for it would be ideal, but Nash says it'd be better for now to work on keeping tapeworms out of the food supply in the first place. He says he's frustrated that we haven't done more: "I see this as a disease that can be treated and prevented. All of this seems to be very feasible, but nobody wants to do anything about it." What would need to be done is to give people who have adult tapeworms living in their intestines medicine to kill the parasites. Also, it's possible to give pigs vaccines that kill the tapeworm eggs once they've swallowed them. Both of these steps would keep the eggs from getting into circulation and would prevent new infections, and yet nobody seems to be motivated to commit the resources necessary to start the process. Maybe, though, as more people become aware of the horrifying possibilities that come from being exposed to tapeworm—after all, even having one in your intestines is pretty damn awful—we'll make it a priority to get rid of the disgusting little parasites once and for all.
Image via Jubal Harshaw/Shutterstock.