Most readers will chuckle or at least smile at the name of this surprisingly common parasitic disorder, but those afflicted with beaver fever won’t be laughing. It's easy to catch, tough to get rid of, and dangerous to operate under its effects.

Wilderness survival is about more than just avoiding unlikely, though terrible events such as cougar attacks or maulings by bears. Of course, it’s important to take precautions to avoid trouble with large animals and even small ones like insects can be potentially life-threatening. With no access to good medical help, a spider bite or venom from a snake can spell disaster. But it’s the little things we can’t see and which modern infrastructure has pretty much stamped out of towns and cities that can pose the most common serious threats to life and health, post-catastrophe.

First world water supplies are managed to prevent the rapid spread of disease by that vector, but water that appears to be clean and fresh at a glance can hide a disaster waiting to happen, even in urban locations, after civilization starts to collapse. Make no mistake: ingesting just 10 microscopic beaver fever cysts can cause serious danger, if left untreated.

First, let’s look at some gear that can help you avoid the threat of water-borne disease and parasites and then we’ll check out one such affliction, so called ‘beaver fever’.

In many situations, it’s just not practical to stop and boil water to sanitize it. Water treatment tablets are an option, but chemical treatment is really a one-shot solution. It’s not the worst choice if you have no other option, but a good portable water filter is vital when you don’t know what’s been squatting upstream from your water source!

Lifestraw offers a very reasonably priced water bottle called the Lifestraw Go with a 2-stage built-in filter that’s good for 1,000 liters of safe drinking. That’s about 264 U.S. gallons, which should hopefully be more than enough to get you by until you can reach someplace where it’s safe to boil and sanitize your drinking water on a more permanent basis. One way to look at it is: you’ve got to carry water with you anyway, so why not just carry a Lifestraw Go and take advantage of the convenience and added safety?

If you’re looking for something a little more durable and solid, yet still portable, there’s the Katadyn Hiker Pro Microfilter. It’s a lighter and more affordable version of the hardcore Katadyn Pocket Water Filter, which will last for 13,000 gallons. That’s almost 50,000 liters for comparison with the Lifestraw Go.

These are all good choices to deal with most common chemical and bacterial contaminants, like beaver fever, encountered in the wild, although even these won’t filter out the smallest viruses, nor will they turn saltwater into drinkable fresh water. Portable filters like these are extremely effective at what they’re designed for, but you’ll still be better off with boiling and full-scale treatment.

So what the heck is beaver fever and why is it worth avoiding? With a name like that, how rough can a dose be?

After the break, learn more about this illness, how to avoid it (drinking contaminated water is only one vector), and how to deal with it if you become infected. Move to the next page to continue: