New Gulf Coast tick species found in suburbs, but 'we don't need to freak out'

A species of tick native to the southeast United States is only recently being found in significant numbers in Illinois, but it's eager to make your acquaintance.

Three Gulf Coast ticks located this month in the Dunham Forest Preserve in Wayne are the first to be found in the Chicago area west of the Cook County lakeshore.

This tick can pursue a potential host it detects nearby and is more likely than others to carry the pathogen causing Tidewater spotted fever, which brings such symptoms as headache, fever, muscle aches, rash and a scab.

But the good news is that the methods of avoiding being bitten are the same as those that keep people safe from other species and the diseases they transmit, said Holly Tuten, vector ecologist for the Illinois Natural History Survey Medical Entomology Lab at the University of Illinois.

"Don't be scared, be prepared," she advised. "We don't need to freak out."

Andres Ortega, DuPage County Forest Preserve District ecologist, echoed that the tried-and-true advice for avoiding ticks is just as effective against this new species.

Staying on the center of trails, remaining vigilant of ticks and wearing protective clothing when in grassy areas are among the ways natural areas can be enjoyed safely, Ortega said.

Discovery of the Gulf Coast ticks' incursion into Illinois is a scientific detective story that's still being written.

Though Gulf Coast ticks were found in Peoria and Madison counties as far back as 1990, fewer than 20 had been identified in the state before last year, Tuten said.

They are similar in appearance to the American dog tick, but the Rickettsia parkeri pathogen that about 20% of the Gulf Coast ticks carry is almost negligible among native species. Yet, the number of people diagnosed with Spotted Fever Group Rickettsioses led scientists to speculate that there may be more Gulf Coast ticks in the environment than were being found.

In fact, but for the addition of a distinctive mark at the bite site, the symptoms of Tidewater spotted fever present themselves as a milder form of Rocky Mountain spotted fever that is commonly transmitted by the American dog tick. Many people are already familiar with the fact that Lyme disease can be spread by the blacklegged or deer tick.

Having identified that Gulf Coast ticks thrived in drier, sunnier areas than other species, researchers devised a new method of searching out them - or "dragging" for them - and 780 were found in Illinois last year, Tuten said.

To date, only adults have been found in the state, suggesting that Illinois winters may still be too harsh for Gulf Coast ticks to spend their entire life cycle here and those that have been caught hitched rides on migratory birds or by similar means.

But Tuten said she has to concede the possibility that an effective way of looking for larvae hasn't been found yet.

With climate change, the northern part of the United States' humid subtropical zone is getting closer to southern Illinois, and Tuten said she'd be surprised if an entirely new population of Gulf Coast ticks was making its way there each year after being wiped out during the winter.

"It's an evolving story," she said.

Ortega said his staff found the three Gulf Coast ticks in two distinct areas of the Dunham Forest Preserve within a few days as a result of random encounters rather than the newly established way of finding them. To him, the fact none were found by dragging seems like an indication their numbers may still be low.

At this stage, practical ways of combating the Gulf Coast ticks' arrival in Illinois haven't been identified, but Tuten said personal protection should be where the emphasis lies. No one on her team received any bites last year, in spite of the many ticks they encountered in the field.

"It is very important for people to be tick-aware in Illinois," she said.

Repellents and permethrin-treated clothing are among the precautions people can take, though she warned that permethrin is toxic to cats.

Her further advice includes making frequent tick checks and looking at one's clothing while outside and afterward. Showering within two hours and washing clothes are also useful, but she emphasized that it's the heat, not water, that kills ticks.

Both Tuten and Ortega said there may be value in holding onto a tick you've found for identification, either if it's bitten you or for research purposes if it's a Gulf Coast tick.

Ortega said any captured tick can be put in a self-sealed plastic bag in the freezer and shown to a physician if symptoms develop from a bite.

Tuten said the INHS Medical Entomology Lab welcomes submissions of photos of actual ticks for identification purposes and to further its research. For information, visit medical-entomology.inhs.illinois.edu/research/free-tick-identifications.

Taking precautions against ticks

The Forest Preserve District of DuPage County advises people to remain vigilant of ticks when in natural outdoor settings and take precautions to avoid tick bites.

• Walk in the center of trails to avoid brushing up against low-lying vegetation.

• If off trail, tuck shirt into pants, roll pant legs into socks or boots and apply DEET repellent to ankles.

• Wear light-colored clothing in order to detect crawling ticks.

• Check your body for ticks as soon as possible after you have been outdoors. Check again the following morning.

• Treat outdoor pets with tick and flea medications.

• If you find an attached tick, grasp it close to the skin with forceps or sharp tweezers.

• Slowly pull it straight out of the bite by the mouthparts. Do not squeeze the tick body, and do not twist or turn the tool.

• Use antiseptic on the bite site after the tick is removed, and wash your hands.

• Save the tick for identification, and observe the bite site closely over the next few days. See your doctor immediately if you get symptoms such as the "bull's-eye" rash, flu-like symptoms, or other musculoskeletal/nervous system deficiencies.

Source: Forest Preserve District of DuPage County