By Linda Alice Dewey
The large brown American dog tick has been around for years. Although it is not benign to its hosts, there’s a new tick in the neighborhood whose bite can be much worse. The black-legged tick, better known as the “deer tick,” is new to Leelanau County. A few years ago, no one thought it was here at all. Now, Leelanau County is one of the counties up and down the Lake Michigan shoreline designated as a high-risk area.
Although other ticks also carry diseases, only the deer tick carries Lyme disease. What’s particularly concerning is that as many as one in four deer ticks are infected.
Of the many diseases ticks can carry, said Benzie-Leelanau Health Department (BLHD) nurse supervisor Autumn Jurek, “Lyme is the most common and most devastating of the diseases.”
For it to be a risk for disease, it has to be attached to the host for 24-36 hours. If caught early, the disease, which is caused by a type of bacteria, can be treated with a round of antibiotics for 10-21 days. Undetected, it can become debilitating.
Health professionals look for a double-ring rash, similar to a bulls-eye, although only 80 percent of Lyme disease patients develop the rash. The rash develops within 3-30 days before the onset of fever. The double ring can be several inches wide, he said.
Remember that spate of very warm weather in early May? Several students showed up at the nurses’ office one day at Glen Lake Elementary school with tick bites, reported Barbara Springsteen. Whether the school’s bites originated on the playground, home or somewhere else is hard to determine, but to have several in one day was unusual, and teachers were advised to be on the lookout.
Two tick species carry the worst diseases for humans—the lone star tick and black-legged “deer” ticks. Although the Centers for Disease Control (CDC) maps show that the lone star tick had not yet arrived in Michigan, some believe it’s now here. But black-legged deer ticks are here in full force.
The Michigan Department of Health and Human Services (MDHHS) website shows they are spreading up Michigan’s west coast and moving east. According to the MDHHS map, most counties along Michigan’s west coast, including Leelanau County, are now high-risk areas.
There’s a reason for that. Deer ticks like sandy soil that has a variety of plant life, so they like Lake Michigan’s shoreline. But give them a wooded area, and deer ticks will also move away from the sand.
Black-legged ticks increased from five counties in 1998 to 24 counties in 2016, according to a story last year in the Detroit Free Press.
However, BHLD’s Crawford said that although it’s fairly common to see ticks now, the county is yet not mapping tick bites. “That may change,” he qualified, “if we get clusters of Lyme disease.”
Dr. Jerry Harrison of Leelanau Veterinary Care also notices the swell in the tick population. “We are seeing more ticks every year,” he said. “Animals by their nature will wander into brush and areas their owners would not go, which is where they are more likely to pick up ticks. Yet they are a sentinel for us.
“If there are ticks on owners’ pets,” he warned, “then what about their children playing in the woods and the owners themselves? Maybe it is time to start doing tick checks for anyone going out in the woods.”
Here’s another scenario to watch for. We hug our dogs and outdoor cats, ruffle their fur, and they come in from outside and lie on our rugs and brush up (at the very least) against our furniture. But what are they bringing in? And what about the danger to their health? Pets can get Lyme disease, too.
The number of cases of Lyme disease in Michigan are up, correlating with the higher number of deer ticks. NatureChange.org, an online magazine devoted to conversations about conservation and climate, stated in that 55 Michigan human cases were reported in Spring 2016 alone.
According to MDHHS, 7 infected ticks were found in Leelanau County that year, (the most recent data available). Unofficially, as of early May this year, none had been reported to LBHD in 2018.
Jean Tsao, associate professor in Michigan State University’s departments of fisheries and wildlife and large animal clinical sciences, said that Lyme disease in Michigan climbed from 30 cases between 2000-2004 to 166 cases in 2013. That number could be low, because doctors don’t always test for it because it’s such a new phenomenon here. In fact, among members of the support group, Michigan Lyme Disease Association, the average member was not diagnosed until two to seven years after initial onset of symptoms.
Dr. Kathryn Krezoski-Evans at Empire Family Care works in Empire and at Munson Urgent Care in Traverse City. “I have seen an increase at both locations,” she said. She feels it makes sense “to anticipate that ticks that are around now potentially could have Lyme disease, because the percentage has been increasing over the last couple of years.”
As far as this year’s rate goes, “We don’t know the rate at which they’re increasing until after the summer. We test what’s happened that summer, then we know, ‘Oh last year there was more.’
Even so, “each year it’s been increasing, so we should assume that it’s continuing to do so.”
Ticks become infected when they bite infected animals such as deer, mice (in particular, the white-footed mouse but also deer mice), chipmunks, birds and domestic animals.
Deer mice aren’t usually seen south of Clare, but the white-footed mouse is a southern species that has been found now in our state. According to NatureChange.org, it probably was not in Michigan prior to 1900, but it, along with other rodent species, has been moving north as the climate has warmed.
Dr. William Scharf, a Traverse City based parasitologist has also found another southern species of tick, usually found in Louisiana and Georgia, at Chippewa Run, near Empire. It was turned up in Kalamazoo, too. Scharf has been doing this since 1968, when finding ticks on birds was highly uncommon. But recently, he found 100 ticks on a bird’s ear. He believes the climate change is causing the birds to fly north, bringing the ticks with them.
Last month was the warmest May on record in the United States, according to the National Oceanic and Atmospheric Administration (NOAA).
Short winters can result in an explosion of the white-footed mouse, Dr. Philip Myers told NatureChange.org. While neither this past winter nor the Winter of 2014 was short by any means, our winters since 1999 have, on average, been becoming shorter and warmer. Although we did have a week of sub-zero temperatures, this year, temperatures rarely drop below 10 degrees any more, a temp needed to kill off some insects.
Other scientists say it’s not the cold per se that kills the ticks (80 percent survive minus 10 degrees Fahrenheit), but the fluctuation between extreme cold followed by a warmer thaw that might kill ticks. Since they burrow into the soil and under leaves in winter, if they’re under a blanket of snow, extreme freezes won’t reach them. That said, nymphs that emerge during a thaw will burrow back in, but possibly not in time to avoid a quick freeze, hence the 20 percent loss.
Whatever the cause, be aware and take precautions. Mother Nature is once again on the move. Deer ticks and Lyme disease have arrived in lovely Leelanau County.