Tick-borne Lyme disease exploding into Michigan; human cases up 5-fold

Tick population rising

EAST LANSING, MICH. - They're already back.

All it took was an unusual February warm spell this past week for the tiny insects causing an increasingly big problem in Michigan to become active once again, beginning their hunt for blood.

"A student in the medical entomology lab just brought in six adult blacklegged ticks — three male and three female — that were collected by his dog (Tuesday) in Lansing," said Jean Tsao, an associate professor in Michigan State University's departments of fisheries and wildlife and large animal clinical sciences.

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►Related: Lyme disease in Michigan: New Washtenaw County case could be evidence of infected ticks

The ticks are of interest because of what they often carry with them: the bacterium Borrelia burgdorferi. When the ticks bite an animal, seeking a blood meal, that bacteria can transfer. And that bacteria, in dogs, horses and humans, can cause Lyme disease, a serious affliction that can be permanently debilitating for people when it's not treated early and well.

Tsao is a co-author of a recently published research paper documenting Lyme disease's rapid spread into Michigan in recent years. There were fewer than 30 human cases of Lyme disease reported in Michigan in any year between 2000 and 2004. By 2009, the number had jumped to 90 reported cases. By 2013, it was 166 cases.

That number could be very low. The federal Centers for Disease Control and Prevention estimates the number of Lyme disease cases nationwide could be 10 times higher than what's actually reported. Because of Lyme disease's relative newness in Michigan, and because its early symptoms often mimic what feels like the flu,infected people — and even their doctors — often don't test for it. Doctors also don't always report finding Lyme disease to their local public health department, said Erik Foster, an entomologist with the Michigan Department of Health and Human Services and a co-author of the recent study.

The Lyme disease spike in Michigan correlates with the spread of blacklegged ticks here. In 1998, the ticks were established in only five counties — Berrien County in the southwestern-most Lower Peninsula, and four counties in the Upper Peninsula — and reported in 22 other counties. By 2016, however, the ticks were established in almost five times as many counties — established in 24 Michigan counties and reported in 18 others. The ticks have overtaken the entirety of the Lake Michigan shoreline in the Lower Peninsula, from Charlevoix to St. Joseph. But tick populations are not staying confined to coastal counties, becoming established increasingly to the east in the southern part of the state.

Tsao is always on the hunt for blacklegged ticks. In spring and summer, she can often be found dragging white corduroy cloth through Michigan forests, checking for the presence of the tiny bugs  — usually only 3 to 5 millimeters in size, but that can grow more than twice that when engorged on a host's blood. In the fall, Tsao and her students often check for the ticks on harvested deer at check stations during hunting season.

These days, the more Tsao looks, the more she finds.

"We know this is a real invasion," Tsao said.

Why the increase?

Why the increase is happening now, scientists can't say for sure. Lyme disease and the ticks that carry it have long been established on the East Coast. In the upper Midwest, states such as Wisconsin and Minnesota have more than 10 times as many human cases of Lyme disease as Michigan.

Tsao's theory is that Lake Michigan served as a natural barrier holding the blacklegged ticks back. But the ticks are capable of being carried across the lake on birds, she said.

"Over time, as the Wisconsin, Minnesota and Upper Peninsula populations grew, that pressure of ticks coming down to places where birds like to stop over would have increased," she said. "In the past, they could have come and died. But eventually, enough of them have arrived, survived the various life stages and began mating.

"Mom, if she gets a nice blood meal, she can lay 2,000 eggs. Nineteen-hundred and 99 can die; so long as one survives to meet another tick from another female, you have the next generation going."

The ticks thrive in sandy areas with varied plant life, which is why they raced up Michigan's Lake Michigan shoreline once established here, Tsao said. The ticks go through three life phases — larva, nymph and adult, and each stage needs a blood meal, she said. They perch on plants and branches, waiting for a host animal to brush by.

"It finds a host, takes its blood meal, falls off into the leaf litter, evolves and finds its next host," she said.

The process can take two to three years for ticks in Michigan, the larvae feeding in year one; the nymph and adult in the second year, Tsao said. Each winter, the leaf cover and snow serve as an insulating blanket until spring.

While croplands farther east in Michigan's Lower Peninsula aren't as optimal for blacklegged ticks, all it takes are patches of woods and herds of deer to continue the in-state spread, Tsao said.

"If you've got nice woods around, and have nice habitat for deer, mice, birds and other species, you could have a little island for ticks," she said.

Ticks have been found in East Tawas on the Lake Huron side of Michigan, as well as in the Thumb, Tsao said.

"I'm not trying to be fear-mongering," she said. "But if you look at Michigan and look at other states where Lyme disease-causing ticks are found, what kind of vegetation is there? What kind of animals are there?

"There's no reason we would not have ticks everywhere."

Missed diagnosis

Heather Feldkamp, 44, discovered her Lyme disease infection too late.

The Saline resident was a very active soccer player when, in January 2013, her right leg started going numb.

"I thought it was sciatica," a pinched nerve condition, she said. "I went to the chiropractor a couple of times. Eventually, my left leg started going numb as well. I was starting to limp. I couldn't play soccer anymore."

Feldkamp said her primary care physician was baffled and sent her to a neurologist, who conducted an MRI. Then came a spinal tap, and the coincidental discovery that she had cancer. She beat breast cancer within that year, but the tingling and impinged motion continued. Her primary care doctor and oncologist thought the symptoms were somehow related to her cancer, but Feldkamp was skeptical.

She went to a holistic doctor in Ann Arbor, versed in Lyme disease, at her own expense. "She tests me and says, 'You don't have cancer in your nerves; you're full of Lyme,'" Feldkamp recalled.

Sharing that news with her other doctors brought pushback, she said. "They told me, 'We don't have Lyme (here),'" she said.

A blood test was shipped to a lab in California. Weeks later, Feldkamp received a call from the Washtenaw County Health Department. "Where have you been? Where have you been traveling?" she said they asked. Her test had come back positive for Lyme disease.

"I hadn't traveled," she said. "I live on a dairy farm. We've got a lot of trees, a lot of cattle, deer."

Feldkamp doesn't recall a tick bite, or the signature bull's-eye rash that often develops after one.

"I could have had it for a year. Maybe it laid dormant," she said. "I was told I could have gotten bit on my head, where you never see the bite, because it's covered by your hair."

Feldkamp said she never got her primary care doctor, neurologist, or oncologist to take Lyme disease seriously. "And once I started being vocal about it on Facebook, I started hearing from all these other people suffering from Lyme disease who've had a similar experience with their doctors," she said.

According to the Infectious Diseases Society of America, taking certain types of antibiotics for up to three weeks is the best course of treatment when Lyme disease is discovered early. Longer courses of antibiotics, possibly administered repeatedly over several months, are called for when the disease is caught later.

More problematic, however, is when tests show the disease is gone, but debilitating symptoms remain, known as post-Lyme disease syndrome.

"There is no well-accepted definition of post–Lyme disease syndrome," a 2006 study published by the Infectious Diseases Society of America stated. "This has contributed to confusion and controversy and to a lack of firm data on its incidence, prevalence and (manner of development)."

There's even debate in the medical community about what causes post-Lyme disease syndrome, Foster said. "Some people say it's still the spirochetes" — the spiral shaped, Lyme disease-causing bacterium — "that are still there, gone into cyst form," he said. "Others say the spirochetes are no longer there, but the initial infection is still causing an auto-immune response, and the body is attacking itself."

The lack of answers, and outright skepticism sufferers can face from medical professional, have led to passionate responses, Foster said. "They're hurting, they want to get to the bottom of these infections," he said.

"People get misdiagnosed a lot," said Christina Emery, 51, of Adrian, who has post-Lyme disease syndrome. Emery is the past vice president of the Michigan Lyme Disease Association, a support group. She stepped down two years ago when her arthritis-like symptoms, seizures and other health problems became too significant, she said.

Emery, her husband and two of their three children tested positive for Lyme disease, but in each case, the infection wasn't detected until weeks, months or years later.

"I know from my time with the Michigan Lyme Disease Association, the average time it took people to get diagnosed with this was two to seven years" after the onset of symptoms, she said.

The state health department makes information available to medical professionals to help them better understand the reality of Lyme disease in Michigan, and how to spot it, Foster said.

Feldkamp remains in remission for cancer, but now needs the assistance of a cane, more than four years later.

"I walk with a limp, my leg's still numb," she said. "But I'm still alive. It is what it is. I've got to keep moving on."

Do a tick check

As the ticks that spread Lyme disease make their way across the state, Michigan residents need to adopt the precautions long in place in Lyme-ridden areas such as New England, Foster said. Avoid areas where ticks are likely present. Use repellents on clothing.

"The key is to make sure when you come back from being in these areas, do a tick check," he said. "Remove the ticks as quickly as you can. Even if bitten, if you can get it off before 24 hours, your chances of getting Lyme disease are almost none."

Take action to help prevent Lyme disease

The Michigan Department of Health and Human Services offers these tick tips:

  • On outdoor excursions where blacklegged ticks could be present, use insect repellent that contains 20%-30% DEET.
  • Wear clothing that has been treated with permethrin.
  • Take a shower as soon as you can after coming indoors.
  • Look for ticks on your body. If a tick is attached to you, use fine-tipped tweezers to grasp the tick at the surface of your skin. Pull the tick straight up and out. Don’t twist or jerk the tick — this can cause the mouth parts to break off and stay in the skin.
  • Put your clothes in the dryer on high heat for 60 minutes to kill any remaining ticks.
  • Hunters and anglers cannot get Lyme disease from dressing carcasses, or eating game meat, but are more likely to be in tick habitats.
  • Pets can become hosts for ticks and also become infected with Lyme disease and other tick-borne diseases.  Topical flea and tick treatments are recommended, and a Lyme disease vaccination is available.  Consult your veterinarian for more information.

Contact Keith Matheny: 313-222-5021 or kmatheny@freepress.com. Follow him on Twitter @keithmatheny.

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