Malaria parasites attacking blood cells.
Malaria parasites attacking blood cells.
Malaria parasites attacking blood cells. (Omikron/Getty)

Little Things That Kill You

When you're outdoors, you tend to worry about grizzly bears, sharks, and mountain lions. But the real dangers are the parasites and microbes you can't even see. Steven Rinella has been felled by the worst of them, and he offers an essential guide to prioritizing your panic.

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If the doomsayers are right and we are headed toward a zombie apocalypse, I’ll have a laugh from the grave about whoever eats me. Unless they cook my flesh to an internal temperature of 160 degrees Fahrenheit, they’re going to experience the same torture that I recently endured after enjoying a meal of undercooked black bear meat in central Alaska that was contaminated with the roundworm Trichinella spiralis. The parasites bred inside me and sent forth untold thousands of progeny to burrow through the walls of my vascular system and into my muscular tissue. The gastrointestinal issues were horrific, but not nearly so nasty as the muscle pain. It felt like a bad weight-lifting accident spread across my entire body. The Pepsi-colored urine that I was passing served as a visual aid to help me understand just how much hard-won muscle I was literally flushing down the toilet. 

Trichinella spiralis.
Trichinella spiralis. (Wikimedia Commons)

The worms were just the latest invaders in a series of microscopic parasites and bacteria that have infiltrated my body in recent years. In terms of severity, the highlight of the run was a bout of Lyme disease, caused by bacteria transmitted through a tick bite that manifested with amnesia and concluded a few agonizing months later with a four-week round of intravenous antibiotics administered through a tube that ran from a hole in my arm to my heart. Preceding the Lyme was a complex case of giardia, an intestinal infection from parasites, that landed me in the emergency room twice in one day and then in a hospital bed for four nights. Following the Lyme was the trichinosis. The larvae of those worms now survive in my muscles, protected by calcified cysts. They have no way of harming me again, though they will make life hell for any creature that digests my uncooked flesh and thereby liberates the legions of pests.

Much of this trouble has come as an occupational hazard. I host a television series called MeatEater on the Sportsman Channel that explores the world of hunting, wild foods, and adventure. I’ve also had a lifelong interest in spending as much time outside as I can, and I’m never happier than when I’m off the grid at my tiny cabin in southeast Alaska, filleting halibut and salmon I caught with my brothers. This lifestyle has brought me up against all manner of threats, including a moose attack, a grizzly charge, and a couple of tussles with wild boars. But it’s the microscopic critters that have proven most effective at putting me on the ground. Trust me: anyone who ascribes to that old adage about not sweating the small stuff hasn’t spent much time outdoors.

Years ago, I went to a lecture by a mountaineer who had recently returned from Mount Everest. During his talk, he discussed a famous study from the late nineties in which researchers instructed subjects to watch a video of six people playing catch with two balls. The subjects were tasked with counting how many times the balls traded hands between the individuals, who were identified by black and white shirts. Meanwhile, in the video, a woman dressed in a gorilla suit walked through the middle of the game. Half of the subjects failed to see the gorilla, thanks to something that researchers describe as inattentional blindness, or a failure to perceive unexpected stimuli that are in plain sight. But the mountaineer offered his own interpretation: those who see the gorilla survive the mountain; those who don’t, do not. 

I’d take that argument further and say that those of us who turn a blind eye to the little things we come across are also courting disaster. Granted, a giardia cyst is only about one-fiftieth the size of the period at the end of this sentence. The larvae of Trichinella spiralis are plenty small, too—you can’t detect them with the naked eye. Trichinosis diagnoses must be reported to the local Department of Public Health, which asked me to provide a piece of the bear meat I’d eaten for testing, in order to verify the cause of my infection. It turns out that the meat contained about 360,000 larvae per pound. That it still looked delicious is a testament to the invisibility of the worms. 

Microthreats are hardly confined to the wilderness. From the common cold to the Ebola virus, various nasties could be waiting to pounce on you every time you shake someone’s hand. But in the outdoors, there’s this whole other league of bizarre and miniature predators desperately wanting to make the jump from the animal to the human world. You could go on for hours trying to name them all: Rocky Mountain spotted fever, leishmaniasis, rabies, malaria, cryptosporidium, hantavirus, tularemia, leptospirosis. 

Steven Rinella.
Steven Rinella. (Mike Washlesky)

I’ve been around enough to have accumulated a basic understanding of most of these ailments, a fact that my wife, Katie, used against me when I contracted trichinosis. “You should be embarrassed,” she said. “I mean, you know about this kind of stuff!” She raised a valid point, which is perhaps the funniest—or maybe the saddest—part of all this: I’d learned about every one of the diseases that I recently caught well in advance of catching them. In the case of trichinosis, I not only knew about the disease, but I had warned others about it through a book, published articles, and several MeatEater episodes. 

With giardia, I had gone so far as to read academic papers about the protozoa. What’s more, I’d already struggled with minor giardia infections on two separate occasions prior to the day that I contracted my most recent case, while filming in Arizona. On that morning, I was standing at the bottom of a canyon in the Galiuro Mountains after spending a waterless night camped on top of a high butte. I dipped a Nalgene bottle into a creek, filled it with some of the most beautiful water on the planet, and dropped in two iodine tablets. You’re supposed to wait about 15 minutes, but I gave it an impatient five and then chugged away. 

About a week later, I was filming a wild pig hunt in Northern California when things started to go seriously wrong in my gut. I carried on despite the rising discomfort and ended up getting a nice boar. But the pig must have been rolling in poison oak—within two days, I was covered in rashes from the waist up and running a fever, in addition to suffering from a case of giardia-induced diarrhea. A doctor put me on steroids for the rash, which wreaked havoc on my immune system and undoubtedly heightened the giardia’s effect on my intestines. Soon I was passing copious amounts of blood in a hospital bed. When I was released four days later, a doctor inquired about any “prevention plans” that I could use on upcoming outdoor adventures. I thought about the gorilla in the study. It wasn’t that I didn’t see this one coming, however small it was. But rather than move out of the way, I opted to let it walk up and beat me half to death. 

One thing I admire about the small stuff is how insidious it is. The delay that separates the infection date from the onset of symptoms can be weeks or months. If you look at things from the perspective of the disease, the time lapse is a shrewd strategy. For one thing, it makes diagnosis extremely tricky. When I got trichinosis, I was shooting an episode of MeatEater that involved taking a Navy SEAL officer on his first hunt. He wanted an intense experience, and I figured that hunting and eating bears in the western Alaska Range would suffice. In total, three crew members and I got sick. There are typically fewer than a dozen reported cases of trichinosis in the U.S. every year; I’m proud to know a significant percentage of this year’s victims. We ate the bear meat on June 6, but the symptoms didn’t hit until the Fourth of July. If we hadn’t been in touch through work e-mails, I don’t think we ever would have put it together. But knowing that we were all having the same experiences helped us narrow down the list of potential causes. Still, just try walking into a doctor’s office and explaining that you’ve self-diagnosed a condition that’s about as relevant today as scurvy. Persuading someone to take you seriously is almost as annoying as the worms. 

I've been around enough to have accumulated an understanding of these ailments, a fact that my wife used against me when I contracted trichinosis. “You should be embarrassed,” she said.

Another result of delayed symptoms is that it makes the condition seem slightly more palatable. When you’re faced with a scenario that might cause you to get sick at some point in the future, it’s easier to take risks than if you could get sick right away. The day that I contracted Lyme disease, I was with a buddy in New York’s Westchester County, about a 45-minute drive from where I was living at the time. It’s one of the nation’s worst counties for the disease: the majority of the area’s black-legged ticks, which transmit the bacterium, are infected. It was June, which is the high season for humans to contract Lyme. I was walking through tall grass on trails made by white-tailed deer, which host the black-legged ticks. Yet I spent the day traipsing around on those trails without taking any meaningful precautions—no deet, no pant legs tucked into socks, no long sleeves—because I was intent on catching some bluegills from a local reservoir to make fish tacos for my family. Would I have behaved any differently if you had told me that 50 percent of the ticks in those woods were capable of rising up and smacking me on the head with a baseball bat? Absolutely.

A month later, I was sitting in my office, and suddenly I had no idea how I’d gotten there. I couldn’t remember waking up or leaving my house that day. I couldn’t account for the words written on my computer screen. When I tried to get home, I couldn’t remember the route. I called my wife, with difficulty, and she took me to the emergency room. Initially, I was diagnosed with something called transient global amnesia; however, a continuation of strange defects in my nervous system—most notably a numbness in my legs that made it difficult to walk—eventually led to an accurate diagnosis of Lyme. The five-month recovery process included a $20,000 course of antibiotics. It’s worth mentioning that I didn’t catch a single bluegill that day in Westchester County. 

Not long ago, while filming in the jungles of Bolivia, I was stung on the ankle by a bullet ant—a gargantuan creature compared with the sorts of things I’ve been talking about. On the Schmidt Pain Index, which rates insect stings, the bullet ant is the only one awarded a four-plus rating, the highest possible score. The entomologist Justin Schmidt, who created the index, aptly describes it as “pure, intense, brilliant pain. Like walking over flaming charcoal with a three-inch nail grinding into your heel.” To me it felt like being stung by a chicken-size wasp, with a deep and throbbing ache that ran from my toes to my knee. I squashed the guilty ant within seconds of it stinging me, not out of malice but to ensure it couldn’t hit me again. For the rest of the trip, I went out of my way to enjoy the sight of any bullet ant that I happened to encounter in the jungle. The species had earned my admiration. 

On the occasions that I’ve been sick from microscopic tormentors, I’ve tried to regard them in the same way that I regard dangerous animals and treacherous landscapes. But hard as I try, I can’t quite bring myself to love the little guys. I respect them, sure, but it’s like how a general respects an opposing force. It’s a respect that is tainted by a desire to see them cleansed from the face of the earth. 

But at what cost would the annihilation come, however unlikely it is? How differently would we perceive the outdoors if it weren’t for that great biodiversity of little bastards hiding in the water we drink, the food we eat, and the bugs that bite us? In the absence of risk, would we find contentment, or would everything taste and feel a little less exciting? In the words of the great conservationist Aldo Leopold, “It must be poor life that achieves freedom from fear.” 

I think back to that meal of black bear meat in Alaska. I can picture it perfectly: a collection of purplish red hunks of flesh suspended above the coals on willow skewers as smoke wafted from below and rain fell from above. Distracting me from the task of cooking was a large grizzly that had been hanging around south of camp. We’d been reveling in the presence of the big bear, but if he was going to show up for dinner I wanted to know well in advance. As soon as the outer surfaces of the meat achieved a nice mahogany color with charred accents, we all popped a few pieces in our mouths and then started the long hike back to the lake where we’d landed a week before on a float plane. Flying out of there, I was quick to miss the palpable sense of danger that makes me feel so gloriously alive when in the wilderness. But now I realize that such longings are completely unnecessary. There’s a good chance that some part of the wild is tagging along, hiding right inside of me.     

Contributing editor Steven Rinella (@stevenrinella) is the author of the forthcoming series The Complete Guide to Hunting, Butchering, and Cooking Wild Game.

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