First came the itching — hives so maddening they made Suzanne Keithley-Myers want to claw her flesh. Then came waves of stomach pain so dizzying and disorienting they made her "kind of afraid for my life."
The 45-year-old nurse couldn't explain her body's breakdown. She suspected it was tied to ticks that had bitten her during a June mushroom hunting trip in the woods near Aurora, Minn., but this didn't seem like a typical tick reaction.
On a hunch, she Googled "meat allergy" and found something that seemed like a perfect fit — a rare, potentially severe allergy to "alpha-gal," a sugar found in red meat, triggered by a bite from the lone star tick.
Adding to the mystery: the lone star tick isn't supposed to be in Minnesota. Yet, in the last couple years at least two dozen people in the northern part of the state have suddenly become severely allergic to red meat.
Dr. Alaaddin Kandeel, an allergist at Essentia Health in Duluth who saw Keithley-Myers, said he's diagnosed the same allergy in 18 patients, including 10 from northeast Minnesota and eight from northwest Wisconsin.
"And I've seen this at least one patient a month with this allergy," he said. "I've had patients who passed out as a result of this, and sometimes it can be fatal as well."
Dr. Chris Cleveland, an allergist at Sanford Health in Fargo, N.D., has seen similar symptoms in a handful of Minnesota patients he treated in Bemidji and Thief River Falls.
"Waking up often in the middle of the night, usually four to six hours after they've been done with their meal, and have very intense itching to their palms and the soles of their feet," he said.
It can spread across nearly the entire body, even swelling the tongue and throat, he added.
Nationally, the allergy has largely been concentrated in the southeastern U.S., where scientists have linked it to the lone star tick.
Diagnoses of the allergy have exploded, from a couple dozen people when it was first identified about seven years ago, to several thousand today.
In Minnesota, it's not clear what kind of tick is triggering the trouble. The lone star tick's range currently stops just below the Iowa border.
"We get sporadic reports of lone star ticks, but we don't know of any established populations because when we've gone out and done our routine tick surveillance, what we really find are wood ticks ... and then those black legged ticks, or the deer ticks," said Elizabeth Schiffman, an epidemiologist at the Minnesota Department of Health.