Everything you need to know about waterborne pathogens, treatment methods and more.
In part two of this series, we’re looking at the pros and cons of UV light, chemicals, combination treatments and boiling.
Viruses take the cake as tiniest of the waterborne disease-causing microorganisms—smaller than both protozoa and bacteria. These nasty little bugs are also the least understood by scientists, and cause the greatest range of symptoms across infected individuals. The good new is, in North American backcountries, viruses are typically considered much less of a concern than the other pathogenic threats.
Bacteria are everywhere—on you, in you, in the soil, and yes, even in the wilderness’ cool, refreshing water sources. In fact harmless species of these single-cell organisms exist naturally in the backcountry’s rivers and pools. But humans and animals can carry harmful bacteria as well, and spread these pathogens to the water, making it risky if you happen to drink from the wrong place at the wrong time. Some of these bacteria are the same notorious headline grabbers associated with foodborne outbreaks or epidemics after natural disasters. We’ll discuss those and others, but first a few general facts.
Research backcountry water treatment and you’re sure to be warned about cryptosporidium or “crypto.” And for good reason. This microscopic protozoan parasite is one of the most common causes of waterborne disease in humans in the United States. Like the parasite giardia, crypto is found in water sources worldwide, and affects individuals differently. Fortunately, the disease it causes is rarely life-threatening in healthy adults. In fact, some 80% of the U.S. population has had cryptosporidiosis at some time, according to the FDA. Still, its symptoms are nasty enough that you’ll want to take strides to avoid it on your next backpacking trip.
If you find the published information about Giardia confusing and inconsistent, it’s because the information is a reflection of the parasite itself. Giardia is a multifaceted protozoan that affects individuals differently. It can be prevalent in one small corner of a lake, and practically absent in other parts of the same body of water. In the context of backcountry water, cases of Giardia are rarely diagnosed or reported and there haven’t been enough scientific studies to understand the risks to backcountry travelers. To further complicate the matter, the symptoms of Giardia are difficult to distinguish from those of cryptosporidium, another parasite.
Whether you’re planning a backcountry trip or an urban adventure abroad—say, an Annapurna Circuit trek in Nepal, or a cultural tour of its capital, Kathmandu—you’ll want to take extra precautions with your drinking water. In many developing countries, both municipal drinking water and backcountry water are prone to viruses in addition to bacteria and protozoa. Bringing a water purification system with you is a smart way to help protect you from viral infections that can jeopardize your health, not to mention ruin your vacation.