I'm certain every hiker has a sketchy water story. You know the one, where you had to filter out of that nasty cattle tank or sketchy cistern with who-knows-what lurking in murky depths below.

‍

During my time as a parasitologist in training, I spent hours studying specimens in the laboratory and reading up on the life cycles of a plethora of parasites. From worms to protozoa, I had to be able to understand their life cycle, their pathology, and their morphology. One of my favorite protozoa (and derpiest looking) protozoa we studied in class was Giardia sp.

‍

Giardia, also known as Beaver Fever, is a bulbous, balloon-like little guy with big suckers that resemble eyes. A cute little guy when in the lab, but a hiker's nightmare when on the trail.

Giardia  is a protozoan intestinal parasite that is spread via food, water, or person to person contact that have been contaminated by infected human or animal feces (and you thought norovirus was the only scary hiker poop disease). 

‍

This gnarly little protozoan takes about 1-3 weeks before terrible symptoms begin. Fever, greasy foul smelling stool, intense stomach cramps, diarrhea, and weight loss are just to name a few. These symptoms can last up to 2-6 weeks in healthy persons, but the symptoms are excruciating and the damage this little guy can do to your gut can be permanent. 

‍

Giardia isn’t even the scariest of the organisms that can live in water. Many other waterborne pathogens including Amoebic dysentery, E. coli, Norovirus, or Cyclosporiasis could take you off trail prematurely or if not treated properly, or cause lifelong damage.

‍

The good news? Contamination of this little parasite is entirely preventable by filtering water!

‍

During my Appalachian Trail thru-hike, I contracted norovirus from human waste contamination. I was symptomatic for two days which impacted my overall performance for two weeks. I was weak and calorie deficient, and my appetite nearly disappeared. 

‍

I was lucky; my symptoms were mild and I was back on trail in two days. But because I don’t want you to experience the dehumanizing act of throwing up and simultaneously sh-- yourself in your tent, let’s bust some water filter facts together…

‍

Filters can add microplastics to your water: False!

Many of us are worried about the microplastics in our water and the overall long term effects of them on our bodies. Hollow fiber membrane filters can reduce the amount of microplastics in your water by removing everything larger than 0.1 absolute microns. For reference, a strand of your hair is about 17 microns wide. 

‍

This process removes 100% of microplastics, and will perhaps leave your filtered backpacking water cleaner than your tap water back home! 

‍

Freezing your filter can impact its function: Fact!

Hollow fiber membrane filters like Sawyer’s should not be frozen while wet and should be kept above freezing temperatures. Ice crystals may damage the integrity of the filter membrane. 

Sawyer uses 0.1 absolute micron pores in their fibers to keep pathogenic organisms out and let clean water through. When a filter freezes, the ice crystals formed may damage the integrity of the filter and allow those larger organisms through.

‍

Drinking unfiltered water is a safe way to boost your immune system: False!

Some folks skip the step of filtering water, citing the belief that increasing the biodiversity of the microbiome in the gut is a good thing. While there is suggested evidence that increased biodiversity can help with immunity, weight loss, and increased athletic performance, most health practitioners (and I!) recommend not putting your immediate health at risk by drinking questionably dirty water. 

‍

If you are worried about your trail diet impacting your gut microbiome, I recommend trying to include trail snacks that are high fiber and are nutrient dense, or carry a daily over-the-counter probiotic when hiking. 

‍

One Sawyer filter can last you a lifetime: Fact!

With routine backflushing, Sawyer filters can last a good long time. While I am not the example, I know plenty of people who are still using the same Sawyer Squeeze after their AT thru-hike. Remembering to back flush your filter consistently and keep it clean will extend the filter's lifespan for thousands of gallons to come.

‍

Norovirus is only spread by touch: False!

Norovirus is a virus spread through food, water, and surfaces contaminated by feces. This is why it is rampant among hikers, because we famously don’t/can’t wash our hands super well. It can also be spread through ill managed privies/septic tanks and bad LNT practices when it comes to pooping in the woods. I contracted norovirus due to an ill managed septic system leaking into a water source I was camping at. As a hiker, generally as long as you regularly use hand sanitizer and a good biodegradable soap to clean your hands during your trip, you will be fine.

‍

Thanks for reading! Head to the comments to bust more myths, or ask any questions you have about Sawyer’s hollow fiber membrane water filters. 

‍