Jungle Microbes

It’s almost legendary among Eco-Challenge elites—the race of 2000—where so many got sick. “They had a river swim in the middle of the race, and of the teams that jumped in, at least one person from each got leptospirosis,” says Lawrence Foster, who helped his Canadian team to a ninth-place finish—only to discover how much it would cost him. Within days of returning to Canada, he developed symptoms, and by the time he saw a travel health expert, he was seriously ill. “I had to crawl into his office with my head below my knees,” says Foster. So sick was he that the doctor called an ambulance, and Foster spent the next several days in a hospital bed in a semi-conscious state. Turns out, he didn’t only have leptospirosis but also dengue fever—a serious, sometimes fatal disease transmitted by mosquitoes.

The severity of his illness took Foster by surprise since he thought he had been prudent, using an anti-malarial while in Borneo and getting checked out medically upon return. Initial blood tests proved negative for any infection. And when a fellow Eco-Challenger emailed from Britain with news he had been diagnosed with leptospirosis, Foster again took proactive action—he went to a hospital, asked to be specifically tested for leptospirosis, then was given the appointment with the specialist. (It was while waiting for the appointment that symptoms erupted.)

Yet it wasn’t just word spreading through the Eco community that alerted officials to the outbreak of the disease among the athletes, which is what it became. In fact, after a number of American athletes began showing up in hospitals with the disease, the U.S. Centers for Disease Control and Prevention (CDC) immediately launched an investigation. Of the 189 Eco-Challenge athletes who were contacted by the CDC, 80 were found to have leptospirosis, which is caused by bacteria found in urine from rodents and other animals that contaminate soil, food and water. High bacterial counts often arise in tropical environments after heavy rainfall, when the jungle floor can turn to muck or rain washes surface soil, with all its contaminates, into any nearby body of water. This is exactly what happened in Borneo, where it rained both before and during the race—so that by the time contestants were jumping into the Segama River it was incredibly polluted. “Looking at the water I knew there was some serious erosion happening,” Fosters says now. “It was brown and full of mud and we were jumping into [it] with our open sores and mouths.” The CDC eventually concluded the river was not the only source of infection, and that athletes had been exposed to the bacteria during “kayaking, trekking or contact with mud along the riverbanks.”

Soil, water and insects are the three major vehicles of dangerous disease-causing microbes that live in the rainforest and tropical environments. With water, it’s often about fecal contamination (both animal and human), says Dr. Kevin Kain, an internationally recognized tropical disease expert, who credits a tip-to-top trip in Africa with sparking his interest in the specialty. Insects are the big player since most jungle diseases are ‘vector-borne’—where a microbe is hosted and then transmitted to one party by another. The most potent disease-transmitting vector is the mosquito—it’s the granddaddy of ’em all, with thousands of different species conveying countless diseases—but so too are ticks, mites, lice, fleas, flies (especially tsetse and sandflies), kissing bugs and leeches, all of which can transmit bacteria, viruses or parasites.

Apart from some specific tips, two key points should be made about vectors in the jungle. Though not every bite will kill you, it’s best to view these little buggers as you would a charging lion. That is to say, avoid them like the plague—which incidentally, was caused in the Middle Ages by tiny biting rat fleas who managed to wipe out millions. Secondly, don’t convince yourself taking precautions will cramp your style. Kain has never contracted malaria, though he’s been in jungles all over the world and has travelled with people who have. This includes being wary of advice that goes against what you thought to be true, as Kain found out when he reached Lake Malawi on his African trek. “The locals tell you there is no schistosomiasis [in it], but it’s basically rubbish,” he says. In fact, thousands of travellers were getting infected.

It’s not actually bad to assume “everything in the jungle is out to get you,” says Foster, who, as an outdoor instructor, tells people to disinfect any cut no matter how minor. Such simple measures can help keep you protected, and if you heed such advice, adds Kain, the odds of getting infected by a parasite that will wander through your brain—or across your pupil like the African eye worm!—are mercifully small.

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