Beaver fever SUCKS

My final morning on trail, I sat in my tent with the bug screen and rain fly open. Nausea and stomach pains roiled in my gut, and I was trying to make a decision about whether to continue west on the trail, or head back east to the safety of a cheap bunkhouse at Gunflint Northwoods Outfitters.

As I sat there, a pack of wolves started howling very close by. I looked west at the low ridges along Howard Lake and felt sure the wolves were just on the other side. I’d never heard wolves howling so close before.

I waded through many water sources during my hike, including this beaver pond on the Border Route Trail. It is possible to get giardiasis from being in water with the giardia cysts.

After deciding to head back east, my fatigue and weakness were bad enough that I really hoped those wolves didn’t decide to come hunt in my direction. With my physical condition weakened, I felt even more vulnerable than usual to the carnivores of the Northwoods. I’ve never harbored any fantasy that I could fight off a pack of wolves. I’ve always counted on their avoidance of humans. My most genius plan, and I always knew it was more a fantasy than a realistic survival strategy, was constantly scanning the woods for climbable trees.

I haven’t climbed a tree since I was a kid. After puberty, my upper body strength evaporated and now I can barely do five push ups.

As I hiked that final morning, waves of nausea and dizziness washed over me, and I felt a deep empathy for the sick and aging prey of the forest. How terrifying it must be for a deer to have Chronic Wasting Disease, and feel their ability to run and defend themselves also waste away.

Every experience in the woods, even the ones that involve explosive diarrhea, can teach you something new.

Weeks after retreating home to my mother’s house in the Twin Cities, I finally found out why I was sick: giardiasis, a.k.a. beaver fever. “Giardia is a microscopic parasite that causes the diarrheal illness,” according to the Centers for Disease Control and Prevention. “(…)While the parasite can be spread in different ways, water (drinking water and recreational water) is the most common mode of transmission.”

Giardia intestinalis a.k.a beaver fever a.k.a. THE ENEMY. Photo by Janice Haney Carr, public domain and courtesy of the CDC

The CDC lists a few common ways to get giardia: backpackers who drink untreated water, making contact with animals who have the disease, making contact with people who have the disease, and more.

If ever diagnosed with giardia, you may get a call from your state’s Department of Health, as I did. That’s how I learned it’s possible to get giardia from swimming or wading through contaminated water sources as well. Due to cold temperatures setting in at the end of August, I hadn’t been doing much swimming, but I was still doing lots of wading through flooded areas. The Arrowhead in Minnesota got a lot of rain in September, and beavers are always hard at work.

Symptoms of giardiasis usually present 1-3 weeks after infection. The Minnesota Department of Health had me list my previous three weeks of waters sources. It was a long conversation involving maps and guides, as I’d filtered water at least 2-3 times a day from backcountry sources.

I’m not sure how I got beaver fever.

I was very careful when I filtered to avoid getting “dirty” water in my clean water bottles, but accidents happen. When temperatures started to get near freezing at night, I’d put my water filter in a plastic bag and tuck it at the bottom of my sleeping bag to prevent it from freezing, but maybe I forgot one night.

I also hiked with someone during that period who believed they had giardia and took medication just before hiking with me. It’s possible I got it from people-to-people contact. I’ve decided during future long-distance trips, I will avoid hiking with anyone who is currently sick or has been sick recently.

Here’s what I can tell you about giardia: IT SUCKS. Big time. It sucks so bad that if I ever get to do a long-distance or long-term outdoor adventure again, I will make sure the medication (tinidazole) for this parasite is in my medical kit before I leave. I had a surprisingly difficult time finding a pharmacy that had tinidazole in stock, likely due to the fact that this disease isn’t very common anymore in America.

The CDC says some people don’t experience symptoms. Lucky dogs. Here are the symptoms I experienced:

  • Bad stomach ache
  • Nausea
  • Extreme bloating and gas (That smelled extremely bad, like rotten eggs and sulfur)
  • Diarrhea
  • Complete loss of appetite
  • Inability to eat more than a few bites of food at a time
  • Fatigue
  • Weight loss

I’m being dramatic now, but I swear I could feel these little bugs inside my gut. I felt like aliens had taken over my digestive system, and broken it.

Getting treated for this illness was its own challenge. The first test my doctor performed for the parasite came back negative. Apparently, this is normal. Multiple tests over multiple days must be done. It was my second test that came back positive, and finally got me the medication I needed. My health insurance didn’t cover tinidazole, and I had to wait 10 days for a special approval.

On the Appalachian Trail, thru hikers seem to expect a bout or two of norovirus. Somewhere in all of my backpacking research, I’d gotten the impression that giardia wasn’t much worse than norovirus, which usually lasts 1-2 days. I was really wrong. Not only can giardiasis symptoms last 2-6 weeks, without treatment, symptoms can come back, according to the Mayo Clinic.

Beaver fever may sound funny, but it sure doesn’t feel fun. I feel bad for any beavers out there with giardia who are trying to build a dams or chew down a poplar tree. They’re having a rough day, I can tell you.

7 Comments on “Beaver fever SUCKS

  1. Sounds awful. This is one experience I’ll let you do for me. For us all. My best friend and hiking buddy, Marie (you met her at Shanty Creek) had Salmonella in college. She was sicker than a dog. Hospital. The whole works. That said, 5 years ago I had some gut infection that they never figured out what it was. They killed ALL my gut bacteria in order to clear it out. Took 4 years for me to get back to normal. Glad you called a halt and got the right medicine.


    • Yes, I’ll gladly take this one for the team. Yikes! Four years?! The more I learn about this little Protozoa, the more I know I made the right call. It prevents nutrient absorption, causes mass cell death in your intestine, causes you to shed electrolytes, all things that would be terrible for a hiker on trail.


  2. Wow. I feel so badly for you. Can’t imagine how miserable or frightened you were. The wolf thing? Yikes! So you are thinking they sensed you were in a weakened condition and were stalking you? I was just in MN last week working on the Kek, and there are beaver ponds everywhere. I wonder how the parasite would enter your bloodstream just from wading through water? I just did this, and you’ve got me concerned now! Wouldn’t there need to be a portal of entry (i.e., broken skin, splashing into your nose, mouth, etc.?). I am pretty fanatical about purifying water out on the trail, carrying multiple methods for doing so. (I treated some foster dogs for giardia years ago, and know exactly what you mean by the odor!) Your post makes me realize one can’t take too many precautions. I’m glad your safe and have really enjoyed following your adventure!


    • Hey Lucie! No, no, I was never worried the wolves were stalking me. After 2,000 miles of solo hiking in the woods and never seeing a single bear or wolf out there, I’m confident they do everything they can to avoid us. But interactions do happen, and feeling so weak made me realize if I did have an accidental run in with a wolf pack, like if they came hunting down the trail in my direction, my ability to executive my “climb a tree” survival plan was even more unlikely than normal.

      I didn’t ask the health department for clarification on the wading issue. I probably should’ve done more research about that. I do believe to get giardia you have to ingest the cysts, meaning they have to get into your mouth. They ask about the wading, I think, because I suppose it’s possible to get the cysts on your pants as you wade through water, for example, and then somehow transfer them to your mouth. My pants got soaked in beaver ponds and other standing water all the time, and honestly I used my pants to wipe my hands off constantly when I was hiking and eating. I’ll be very careful in the future to make sure I wash my hands before eating, and won’t wipe them on my pants, etc.

      The fact that I thought I was doing everything recommended to prevent getting water-borne illnesses and still got one does mystify me a bit. I have no idea how I got it, really. There are a lot of risks we have to accept as outdoors people: lyme disease, dangerous storms, sudden floods, heat-related illnesses, etc. Some of those things we can do things about. Others I think we just have to accept are a risk we take, the same as we accept every time we get in a car that car accidents kill on average 40,000 people a year in this country.


  3. Glad you are feeling better and that you can use your experience to educate future hikers. You’re awesome and I know you’ll be back out there again!


    • Thanks, Stacey! One of the trickiest parts on a long-distance hike is trying to assess illness when it sets in. Usually, you’re not feeling terrible yet, but you know you’re getting sick. When it’s a disease you haven’t had before, it’s almost impossible to know for sure what’s coming. Yes, hopefully listing the symptoms for others will help them assess accurately when it’s time to run out of the hills and back to the bunkhouse.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: