Lean-tos provide some of the comforts of home in the Adirondack backcountry – a respite from inclement weather, and a comfortable place to cook, eat and socialize. Unfortunately, a potential hidden danger lurks in every corner, and hikers may be unintentionally contributing to the problem.
The threat is the Hantavirus, a nasty virus in the Bunyaviridae family. These viruses infect, but leave unharmed, a variety of local rodent species. Unfortunately, the virus can produce a potentially fatal disease in humans, brought about by contact with rodent urine, saliva or feces. Deer and white-footed mice are frequent visitors to Adirondack lean-tos.
This is no late Halloween horror story; the possibility of Hantavirus is not unheard of in the Adirondacks. Several years ago, a hiker bitten by a mouse in a lean-to may have contracted an infection from the deadly virus. Despite my own skepticism about this particular incident, the potential for an infection exists in the Adirondacks. Based on what I witnessed at a couple lean-tos this past summer, this risk may be growing.
The Hantavirus risk became apparent to me during a late summer trip into the Five Ponds Wilderness. Unlike my usual backcountry trips, this was no bushwhacking jaunt; instead, old logging roads, unmarked herd paths and a few state marked trails provided access to areas I had not visited for several years. The lean-tos at Sand Lake and Wolf Pond provided comfortable accommodations.
Lean2Rescue rehabilitated these same lean-tos some years ago and mostly cleaned them out, including clearing everything underneath. They used to have an odd assortment of junk stuffed under there – everything from discarded underwear to bundles of sticks.
This clean-up did more than just make the lean-tos a more attractive place to camp, it also made them less attractive to mice. Without the cover of branches, old footwear and other assorted debris, these shelters became much less hospitable to mice, reducing the probability of inhaling their potentially Hantavirus-laced urine and feces.
Unfortunately, people are once again stuffing things underneath these lean-tos. Branches, twigs and other woody debris are once again finding their way under these lean-tos, or in the case of Wolf Pond, in the lean-to itself. Although it may feel conscientious to others arriving later, woody debris should not be left under or in a lean-to, where it produces conditions where mice can feel comfortable and secure.
This wasn’t an immediate concern of mine until I returned home. It appears I brought something back other than duff, photographs and memories. Within a week of my trip, a nasty virus invaded my respiratory system. My hypochondria engaged, and I thought: Hantavirus!
Cluttering-up the space underneath the lean-to was not the only way hikers are courting possible danger with Hantavirus. Between the two lean-tos I stayed at there was a pair of tennis shoes, a tangle of nasty smelling rope and some shredded toilet paper. These articles provide shelter and insulation for mice.
In my many years of trail hiking, I never left anything behind in a lean-to. Some people may think it is considerate to leave behind unneeded toilet paper, matches, foodstuffs and other assorted items, but in reality they are just providing rodents another excuse to put up shop and spread their urine and feces in a place where other hikers will be sleeping.
Removing the shelves within lean-tos would probably alleviate much of this problem, thus reducing convenient places to leave stuff behind. It appeared this solution was attempted in the Sand Lake lean-to, but unfortunately, someone wedged in two-by-fours to provide makeshift shelving. Leave no Trace principals should also apply to stuff left behind in lean-tos, including so-called improvements.
Brooms are often found in lean-tos, but sweeping out a lean-to could put someone at serious risk of catching Hantavirus, as it aerosolizes dried mouse urine and feces. Lean-tos should probably be swept only just before leaving (as long as no one is waiting to use it). Using only long-handled brooms might provide some added protection, as would wearing something over your nose and mouth as a filter for aerosolized particles of mouse feces and urine that may contain Hantavirus. Either that, or avoid sweeping altogether.
If an outbreak ever arises from Adirondack lean-tos, it may be necessary to take even more extreme steps like sanitizing remote lean-tos or even removing them altogether. I hope such extreme measures would never be necessary.
Unfortunately, the habits of many lean-to visitors are making these shelters more hospitable to mice that may carry the deadly Hantavirus. We should all adopt a new lean-to etiquette, rather than jeopardize the lean-to tradition we all enjoy.
Not to mention, that it would also reduce the anxiety around this issue for all of us backcountry hypochondriacs.
Photos by Dan Crane: Sand Lake and Wolf Pond lean-tos.