"Trekking Afoot: Stroll, Ski, Scramble, Snowshoe" Archives

May 17 2017

The Threat of Tick-Borne Disease to Cyclists, Campers, Hikers, and Paddlers by Tamia Nelson

Global warming and mass tourism are breaking down barriers to the spread of formerly rare diseases born by ticks. If you’re a bacterium, a protozoan pathogen, or a virus, this is good news. But if you’re a cyclist, camper, hiker, or paddler, it’s not so great. Is the spread of tick-borne disease a tick(ing) time bomb?


To make a long story short, in early spring last year I picked up a hitchhiker when on a short hike through deer country. Here she is in situ:

Sister Traveler in Situ

It’s not a great photo, so I’ve outlined her body in the accompanying black-and-white shot to make her easier to see. She’s wasn’t much bigger than the head of a straight pin. The bruise left by her excavations was three times as large as she was. And yes, she was a “she,” a female deer tick (Ixodes scapularis). The proportions of the scutum (the dark dorsal “shield” visible in the photos below) give the game away.

A Parting of the Ways

As you can see, we parted company before she could drink her fill. Her comparatively svelte figure tells you that. Now here’s a closer look at a second tick — Farwell plucked this one from his thigh a couple of years back — displaying the belly of the beast:

A Ventral View

The saw-like hypostome, visible in the upper right of the photo, is the tick’s sheet anchor, and because Farwell’s clumsy surgery left the shielding palps behind — he dug them out of his flesh later — you can get a particularly good view of his wee tormenter’s barbed holdfast. That toothy hypostome also explains why removing a tick can be a rather, er, ticklish job. The sawteeth serve the same purpose as the barbs on a harpoon. But so deft is the little beast that her initial thrust is painless. At least it was in my case.

I scrubbed the skin around the wound with isopropanol, and the next day I headed off to urgent care for a prophylactic dose of doxycycline. I had more luck than I deserved. A Lyme titer run on blood drawn five weeks later was negative. It seems that Nemesis was content to let me off with a warning. This time.

ARE YOU FEELING LUCKY?

Or would you rather take steps to avoid trouble in the first place? I bet I know the answer. And you’d be right to prefer prevention to cure.

Previously unaffected regions of the States and adjacent Canadian provinces are no longer a safe haven from Lyme disease and other tick-borne infections. The northern latitudes are warming up fast, and the ebb and flow of global tourism ensures that no infectious disease can remain confined to one location for very long.

Moreover, Lyme disease is far from the most serious tick-borne malady. Rocky Mountain spotted fever has already spread well beyond the bounds suggested by the name, and the Powassan virus — first reported in Powassan, Ontario, this virus can cause a deadly tick-borne encephalitis — is already established in tick populations throughout eastern Canada and the northeastern and midwestern United States. The upshot? We’ll be hearing a lot more about ticks in the years to come. So …

THE CLOCK IS TICKING

Suddenly ticks were big news. As the world slowly warms up, tick-borne diseases are being seen in places they haven’t been noticed before. Lyme disease-infected deer ticks were virtually unknown in New York’s Adirondack Mountains in 2005. Now they’re commonplace. Their steady northward advance continues, too. In short, we can’t run, and we can’t hide. (Unless we want to live life in a La-Z-Boy, and even then, we’d need to keep a close eye on Fido. Is he Breaking Bad?)

Still, you’re safe while ON and IN the water. Ticks aren’t aquatic. And neither are we. So whenever you need to meet nature’s call by parking your bike, leaving your boat, or stepping off trail to “water the bushes,” chances are good that ticks are waiting to welcome you. Camping in the wild? It’s dinner time for ticks!

TICKS ARE HARDY AND HARD TO SPOT

The six-legged larvae are smaller than a poppy seed. The eight-legged nymphs aren’t much bigger. Adults aren’t exactly megafauna.

Life Stages of a Deer Tick

The nymphs and adults cling to vegetation with their rear legs, extending their clawed forelegs in what some lyrical boffin has labeled questing behavior. When a suitable host passes by — be he a mouse, a moose, or a man — the leggy tick grabs hold and hangs on. Which is why every prudent person takes precautions. In other words, Be Prepared! You’ll find some suggestions at the CDC website.

In a hurry? Then here’s the executive summary:

  1. Wear long pants and a long-sleeved shirt when afield. Light colors are best — they make it easier to spot a prospecting tick.
  2. Pull your socks up (over your pants legs), and wear a hat with a wide brim. If you want extra protection, you can get clothing impregnated with permethrin, a highly persistent synthetic pyrethroid that kills ticks and mosquitoes on contact. But it also kills fish and aquatic invertebrates, and it sickens cats.
  3. If you have less enthusiasm for total environmental warfare may wish to eschew permethrin in favor of repellents like DEET or picaridin, a newish alternative.
  4. At day’s end, inspect your body. Give special attention to hairline, ears, armpits, groin, and the cleft between your cheeks. If you’re not a contortionist, you’ll probably need to ask a family member or friend to help. Don’t be shy. Then head for the showers. And be sure to wash your hair.

WHAT IF YOU FIND A TICK?

Remove it. Fine-point forceps will do the job, or you can use a “tick spoon.” (I followed the advice described by the University of Maine Cooperative Extension.) Dispatch the tick in the campfire or retain it to show the doc. Owners of alcohol cookers like the Trangia have an advantage here: They have a ready supply of preservative.

Once you’ve dislodged your unwanted guest, it’s just a matter of waiting to learn if you’ve been infected with a tick-borne pathogen. This isn’t as straightforward as it sounds. While the bull’s-eye rash often seen in Lyme disease is now a staple of summer recreation stories in local papers, it’s absent in a large proportion of cases, and the early symptoms of the “malaria-like” babesiosis (an increasingly common co-infection) are subtle and easily missed. That said, if you can see a doc within 72 hours, you can get a prophylactic dose of doxycycline to forestall Lyme disease. But be warned: This will do nothing to protect against babesiosis or tick-borne encephalitis.

Of course, if you’re halfway through a Big Trip, you may be days (or even weeks) from sivilization. The best advice in this case? Get to a doc as soon as you can. Then do as she tells you.

AREN’T THERE VACCINES?

It would be good to know that effective vaccines were readily available. But the only Lyme disease vaccine licensed for human use in the United States was withdrawn from the market in 2002. (If you’re a dog, however, you’re in luck. You have your choice of three. It’s a dog’s life, right?) There are also vaccines against Eurasian tick-borne encephalitis available in Canada and Europe, but none is licensed in the United States, and the value of these vaccines against Powassan virus is unknown. That’s unfortunate, since Powassan encephalitis kills one in ten afflicted individuals — older people would appear to be at greatest risk — with half of the survivors suffering severe, permanent neurological injury.

This makes rather grim reading, I admit. Perhaps you think I’ve exaggerated the risk posed by tick-borne diseases. And perhaps I have. It’s hard to know. At its best, the epidemiological data we have is spotty and unreliable. For instance, it’s estimated that the number of cases of Lyme disease reported to the CDC is only ten percent of the true number. Which means that, for now, the only useful rule of thumb is what I’ve sometimes called the “Fletcher Principle”:

IF IN DOUBT, DOUBT

Consider this: Our knowledge of the distribution of tick-borne pathogens in North America is far from complete, and statistics about the incidence of many tick-borne diseases in humans are little better. And as I said, appropriate vaccines are either hard to come by or nonexistent. So we have no choice: If in doubt, doubt.

Does this mean we should tread fearfully whenever we step foot away from the clear, well-trod path? Good question. For my part, I’m not ready to don a hazmat coverall when I leave the house. But I’m a lot more careful than I used to be. The climate clock is ticking, and it ticks for all of us.

This article was adapted from one originally published on 7 June 2016 at Paddling.net.


Further Reading

 

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Mar 14 2017

A Primer on North Declination & Variation by Tamia Nelson

A magnetic compass is a simple instrument. Or so it appears. A needle or card, a graduated housing, maybe a lanyard ring… And that’s that. It doesn’t beep or chirp, it boasts no colorful map display, and it won’t tell you how far it is to your lunch stop. But twist and turn the compass as much as you like, and the needle (or card) continues to point toward the north. Magic? No. Magnetism. And before some physics Ph.D. takes me to task for playing fast and loose with the truth, I should add that the compass needle doesn’t really “point” north. Its orientation is determined by the north-south lines of force established by the earth’s local magnetic field. Still, the result is the same. The needle…er…points north.

What’s that? You’re not impressed? You say your GPS can do this, too, plus show you exactly where you are on the map? Right—though unless your GPS also incorporates a fluxgate (electronic) compass, it will lose track of north just as soon as you stop moving. Nonetheless, by comparison with the all-seeing, all-knowing GPS, the magnetic compass is a one-trick pony.

But what a trick! This simple, trembling needle—a Chinese invention, by the way—gave medieval Europe the key that eventually unlocked all the rooms in Gaia’s great house. That’s no small achievement. And the compass still has a place in paddlers’ packs—or better yet, on their decks and in their hands. A compass is self-powered and self-contained. It doesn’t depend on satellite coverage or batteries, and it’s not subject to sudden, inexplicable crashes. Every electronic device I’ve owned has failed me sooner or later, almost always without warning. No compass has ever let me down.

As simple and straightforward as a compass appears, however, it holds a dark secret. Its north is not the cartographer’s “true” north. Its needle doesn’t point the way to the soon-to-be open waters lapping around the North Pole. And therein lies a story: the story of the other north pole… Read more…

Two Norths

Originally published at Paddling.com on March 14, 2017

Mar 07 2017

Yes, It’s True: They CAN Shoot You From Shore by Tamia Nelson

Many years ago—William Jefferson Clinton was still living in the White House, and Farwell and I were just starting to write weekly columns for what was then Paddling.net—I was skimming through a not-very-good book on waterfront photography when I came to a chapter titled “You Can Shoot Them From Shore.” The subject was photographing boat races with long lenses, but I couldn’t help thinking that the title hinted at another, darker meaning. And no, I wasn’t being alarmist. I’d already come under fire when I was on the water. (I’d been threatened at gunpoint when hiking in woods, too, but that’s another story.) A young man—the son of a neighbor, as it turned out—decided to amuse himself by sending a few rounds over our heads as we took the canoe out on the ‘Flow for an evening paddle. He’d apparently concluded that he could shoot us from shore with complete impunity. He was right, too. The long arm of the law often proves to be pitifully short in the Adirondack foothills. The “jes’ havin’ a little fun” defense may not figure prominently in the statute books, but it commands respect from many rural cops and courts to this day.

In any event, we escaped unharmed from the shoreline shooter. (It helped to have a bowman with no small experience in assessing—and evading—incoming fire.) Nor did the incident recur. But it served to remind me that paddlers can easily pass for sitting ducks. Deliverance may have been fiction, but almost any one of us could someday share Drew Ballinger’s fate.

I hasten to add that this isn’t very probable … That being said, there’s still a chance that you’ll someday find yourself on the wrong end of a gun. What then?… Read more…

You Don't Want to Confront This

Originally published at Paddling.com on March 7, 2017


Further Reading

 

Questions? Comments? Just click here!

Feb 01 2017

Our Readers Write About the Knives in Their Lives
by Tamia Nelson & Farwell Forrest

Article by Tamia Nelson and Farwell Forrest

Since the last time “Our Readers Write” aired, General Winter’s troops have occupied our corner of of the country, roads have been repeatedly plowed, salted and sanded, and the streams have lapsed into a frozen silence. But while it may be the off‑season for cyclotouring (at least here) and paddling, we’re still busy. We go into the woods when we can, work when we must, and whittle away at our long list of oft‑postponed chores. And we read and answer the e‑mails you send us. That’s always a pleasant interlude.

Here, then, is a selection from the mail Tamia got in response to “What Makes a Perfect Knife?” The article is a couple of years old now, but the subject is as timely today as it was then, and we trust you’ll enjoy these e‑mails as much as we did, beginning with one reader’s advice to buy the best knife you can afford… Read more…

Published in full at Paddling.com on 31 January 2017

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