‘Explosion in ticks’: Doctors, EPA warn of climate change’s impact on health in Wisconsin
Health professionals and the Environmental Protection Agency warn that Wisconsin may owe the spread of tick borne illnesses to climate change. Health professionals and the Environmental Protection Agency have warned that climate change in Wisconsin may have contributed to the spread of tick borne illnesses such as Lyme disease, which is spread through deer tick bites in multiple states. The EPA highlighted the importance of protecting individuals from ticks in the wild by applying insect repellent, but emphasized the need for action on a global level. The World Meteorological Organization stated that the planet has warmed 1.45 C on average over preindustrial temperatures. The average number of Lyme disease cases in Wisconsin has more than doubled in the past two decades. The data tracked by the EPA shows that cases nearly doubled between 1991 and 2018, with New England states seeing the largest increases. Researchers have also noted repeated sightings of the lone star tick throughout Wisconsin.
Published : a month ago by JT Cestkowski in Environment
MADISON (WKOW) – Health professionals and the Environmental Protection Agency warn that Wisconsin may owe the spread of tick borne illnesses to climate change.
“The climate change that we're seeing definitely has been the reason for this explosion in ticks, as well as the increase in human diseases,” Doctor Gregory DeMuri, a pediatric infectious disease physician, told 27 News.
DeMuri underscored the importance of taking measures to protect oneself from ticks in the wild by applying insect repellent. However, he also advised that individual action can only go so far.
“On an individual level, protect yourself against insects,” DeMuri said. “On a global level, we need to do something about climate change.”
Multiple health professionals and government agencies have linked one disease in particular to climate change.
The EPA warns that Lyme disease, commonly spread through deer tick bites, has become a marker of climate change as cases have grown in multiple states, including Wisconsin.
The condition’s symptoms include, fever, headache, fatigue and rash. In serious cases, the infection spreads to the joints, the heart and nervous system, according to the Centers for Disease Control and Prevention (CDC).
“Studies provide evidence that climate change has contributed to the expanded range of ticks, increasing the potential risk of Lyme disease, such as in areas of Canada where the ticks were previously unable to survive,” the EPA website reads. “The life cycle and prevalence of deer ticks are strongly influenced by temperature.”
The planet has warmed 1.45 C on average over preindustrial temperatures, according to the World Meteorological Organization.
The Wisconsin Initiative on Climate Change trends said in 2019 that warmer temperatures will lead to milder winters in the Badger State that will be four weeks shorter on average by the middle of the 21st Century.
“Because tick activity depends on temperatures being above a certain minimum, shorter winters could also extend the period when ticks are active each year, increasing the time that humans could be exposed to Lyme disease,” the EPA wrote.
Nationally, the data tracked by the EPA shows that Lyme disease cases nearly doubled between 1991 and 2018. New England states have seen the largest increases in cases. Outside of the northeast and Mid Atlantic, Wisconsin and Minnesota have also experienced their own growth, according to a map based on information from the CDC.
The Wisconsin Department of Health Services (DHS) reported that the average number of Lyme disease cases in the Badger State have more than doubled in the past two decades.
“Wisconsin is one of the states reporting the highest number of cases each year,” the DHS web page on Lyme disease data says. “The actual number of Lyme disease cases in Wisconsin is likely to be higher than reported.”
But Lyme disease is not the only condition carried by ticks and deer ticks are not the only eight-legged vampires at work.
Researchers have documented repeated sightings of the lone star tick throughout Wisconsin in recent years.
As recently as 2011, the species was not thought to make its home this far north, according to a map of their range published by the CDC.
The species is distinguished by its brown body with a small white spot or star on its back.
It’s found primarily in the southeastern U.S. However, a map published by the UW-Madison Department of Entomology documents lone star ticks found in multiple stages of growth in counties across Wisconsin between 2006 and 2022.
“It does not mean that lone star ticks are established and breeding in these counties,” the department’s web page on the species says. “Most likely, a few ticks are brought into Wisconsin on migrating birds each year, persisting through the summer but not through a Wisconsin winter.”
Many of the sightings come in the southern half of Wisconsin. Most counties have a single documented instance of a lone star tick. Dane County leads the state with 27.
“The signs are telling me that they are close to established if not already established in the southern part of the state,” UW-Madison Entomology Professor Susan Paskewitz was quoted as saying back in 2013.
“What we know is that the lone star tick is in our neighboring states,” Katherine Young, an agroecologist, said. “In Minnesota, it's been identified in Illinois, it's been identified in Michigan.”
The lone star tick’s bite is also associated with a health condition that the medical community is still attempting to fully understand: Alpha-Gal Syndrome. The affliction is an allergy to a sugar contained in red meat and dairy products.
“I started to go into anaphylaxis on a weekly basis,” Young said. She has suffered from Alpha-Gal since an encounter with a lone star tick while working in Central America between 2006 and 2007.
The tick’s bite and subsequent diagnosis upended her life. She is cognizant of everything that goes in or on her body. Despite sharing a kitchen with others, she cooks with her own special pan to avoid cross contamination.
“Mammal products, and particularly, their byproducts are commonly found in many common foods and supplements, including life-saving medications, in the form of lactose or gelatin, that also shows up in things like red wine,” Young said.
Her case has proven severe, developing mast cell activation syndrome. According to the American Academy of Allergy, Asthma and Immunology, the condition triggers some allergic symptoms even when the allergy’s trigger is not present.
“I miss the days when all I had to worry about was avoiding all mammal byproducts,” Young said. “My life became 100 times more complicated with mast cell.”
To help her treat the condition she is taking a drug used on some cancer patients.
“It's extremely hard on the body, and side effects are very similar to mast cell flares,” Young said. “So in my case, extreme fatigue, extreme brain fog, excruciating bone pain, and a sense of my bone crushing vise-like grip, with neurological symptoms that feel like my nerves have been dipped in acid. There's nothing I can take to relieve that pain.”
Alpha-Gal syndrome remains a rare condition, though as medical understanding has caught up more and more cases have been identified.
Research published by the CDC last year found over 90,000 positive test results for Alpha-gal between 2017 and 2022. The research included dozens of positive tests throughout Wisconsin.
The spread of the lone star tick concerns Young from an economic perspective, as its bite can potentially make some of America’s Dairyland allergic to animal products.
“If even a portion of our populace suddenly becomes allergic to our greatest agricultural asset, we have a lot of adaptation strategies that we need to address.”
Young believes that her expertise as an agroecologist could offer some potential escape routes for Wisconsin from both tick-borne illness and climate change more generally.
She sees land use around housing developments as particularly important. When farm fields are left fallow, waiting for the construction of new homes, invasive plants like buckthorn take over. The underbrush and depleted agricultural soil is a haven for ticks.
A study published this past December identified common predators of ticks. Despite their ubiquity, little is known about what creatures prey on ticks and keep their populations in check. The research found that in the case of european ticks, several common species of soil-dwelling predators like spiders, beetles and mites fed on tick nymphs.
“And these predators and the tick nymphs are found in the leaf detritus,” Young said, before elaborating that healthy soils would mean reduced tick populations. In Wisconsin, health soils are usually rooted with diverse, native plant species.
Those roots and stalks in turn sequester carbon that would otherwise end up in the atmosphere, contributing to global warming.
“Seldom do people think about the impacts of the change in the climate, and specifically how that could affect them or their loved ones,” Young said. “I want people to care, because if this can happen to me, this can happen to anybody.”
Topics: Climate Change, ESG