Tick, Tick, Tick...

One morning last summer, Kevin Stephan woke up to find one side of his face numb. “Then, within a week, the numbness had spread to my right arm,” Stephan recalls. “Then there was clumsiness—I couldn’t type, I’d miss the phone when I’d reach for it, and I’d run into the frame of the door. My right leg became so uncoordinated I couldn’t walk in a straight line.”

Stephan is a physician—he chairs the infectious disease department at the Duluth Clinic—but neither he nor his colleagues could figure out what was wrong with him. The results of an MRI suggested that a stroke was at least a possibility; multiple sclerosis was likewise not out of the question. But Stephan, who was forty-three, physically active, and in excellent health, had none of the risk factors or a family history that would indicate either. As it happened, Stephan had been seeing a growing number of Lyme disease patients in his practice—by his estimate, at least 500 cases in the previous three years. And while his symptoms weren’t typical, Lyme was proving to be a disease to which “typical” didn’t typically apply. So he ordered a blood test. But even after the test came back positive, the debate continued. “Should we call it Lyme, or shouldn’t we?” he says, summarizing the discussion. “Eventually, that diagnosis prevailed.”

Stephan was one of more than 1,230 new Lyme cases reported in Minnesota last year, which doesn’t seem like such an alarming figure until a state epidemiologist tells you the number represents about a 35 percent increase over the previous year—and that the number has been rising steadily since the state began tracking cases in 1982 and has risen precipitously since 2001. Worse, some experts and observers posit a factor of ten when attempting to determine an accurate tally, meaning, in Minnesota, there may have been as many as 12,000 new human Lyme infections—most of them undetected, misdiagnosed, or unreported—in 2007. Wisconsin reported more than 1,800 cases last year, up from about 1,460 in 2006.

Minnesota and Wisconsin (where an estimated 20 percent of Minnesota cases contract the Borrelia burgdorferi bacterium) are among the top dozen states in numbers of Lyme cases. That’s because the disease’s vector—the very small and insidious deer tick (sometimes called the blacklegged tick), which carries the bacterium—is most commonly encountered in or near hardwood forests, home to deer, mice, and the tick’s other warm-blooded hosts, and states in the Northeast and eastern Upper Midwest have a lot of hardwood forests. Minnesota’s hardwood is concentrated in its central, eastern, and southeastern counties, though Stephan says he’s treating more and more Lyme patients from Ely, International Falls, and other points way up in coniferous territory. And, while portions of Anoka, Washington, and Ramsey counties are prime deer tick areas, Metropolitan Mosquito Control District researchers have found “isolated populations” in every metro county.

It wasn’t a coincidence that Stephan first noticed his symptoms this time of year. May through July is the period when the bloodsucking arachnids—deer ticks are eight-legged arthropods related to spiders and mites—are feeding in greatest numbers and mammals, including humans of both sexes and all ages, are thus most vulnerable to the often perplexing and increasingly controversial disease that didn’t even have a name until thirty years ago.

Since it was first identified in the United States, among residents of Old Lyme and other leafy communities of southern Connecticut in the mid-1970s, Lyme disease has been wrapped in mystery, confusion, and growing contention.

While only a generation ago the condition was virtually unheard of in the Upper Midwest, now it’s a rare Minnesotan who, if he hasn’t contracted it himself, doesn’t have at least a couple of acquaintances who’ve had a brush with it. A neighbor and the husband of a colleague—Minneapolis residents who own cabins in central Minnesota—have both had Lyme in the past few years, one of them twice. A friend who’s lived in rural east-central Minnesota for decades became one of the state’s first diagnosed patients when a visiting researcher at the Mayo Clinic, pondering the cause of the man’s painfully swollen knees, made the call in the early 1980s. Years ago, the man says, the condition seemed rare and freakish, even in his neck of the deciduous woods. “Now, to hear people talk, it’s as common as the cold up here,” he says. He believes, moreover, his own Lyme has manifested itself several times since that initial diagnosis.

Most Lyme cases, if caught early, are effectively treated. After a weekend at the cabin, a patient shows up at a clinic with a small red bite, or the attached or imbedded tick itself, or a “bull’s-eye” rash (erythema migrans), which may prefigure or accompany flu-like aches and pains and fatigue that often develop within a few days or weeks of the bite. The doctor may order a blood test. If Lyme is diagnosed, two to four weeks of a common antibiotic such as doxycycline or amoxicillin will usually be prescribed, and, in maybe nine out of ten patients, the symptoms disappear.

Unfortunately, the process doesn’t always work that way. Patients overlook or ignore the tick bite, then attribute their symptoms to the flu or overexertion or, in some cases, to more serious conditions such as MS or amyotrophic lateral sclerosis. A doctor, if one is consulted, may find no rash (Kevin Stephan had none, and, according to experts, a rash isn’t present in from a fourth to a third of all Lyme cases) and misdiagnose or dismiss the symptoms, which are often vaguely “nonspecific” and can be attributed to any number of other causes—or to the patient’s imagination. Lists of symptoms blamed on Lyme number well over 100. Individual symptoms can vary widely from patient to patient, affect virtually any part of the body, come and go, and run the gamut from merely annoying (mild headache and chills) to debilitating and life-changing (neurological, heart, and lung complications, memory loss, severe depression, extreme fatigue, crippling arthritis). Then again, what’s making you feel like death on a stick after a weekend in the woods may not in fact be Lyme, even if you’ve been bitten—the Minnesota Department of Health estimates that “only” a third to a half of the deer tick population carries the Lyme infection. On the other hand, a single tick may carry multiple infections, including, in our part of the world, less common but potentially serious babesiosis and human anaplasmosis. And even though you’ve had Lyme, you can contract it again. If left untreated, Lyme can cause devastating long-term problems involving the heart, nervous system, muscles and joints, and other parts of the body.