Ticks Expand Across Illinois: Climate Change and Health Impacts

Scientists and researchers are observing changes in tick season in Illinois, with ticks appearing earlier, staying longer, and spreading to new areas. Milder winters and earlier springs contribute to their survival, and cases of tick-borne illnesses are being reported sooner than in past years. Ticks are no longer confined to heavily wooded areas; they are increasingly found in city parks, green spaces, and suburban yards. Dr. Kelly Cairns, president of the Chicago Veterinary Medical Association, emphasizes that ticks are not restricted to forests and can be found in urban environments.

Tick season traditionally runs from April through September. However, human-driven climate change is causing warmer temperatures year-round, with winter temperatures rising at a faster pace than other seasons. This has led to the growth of tick populations, particularly in the Midwest and Northeast. Patrick Irwin of the Northwest Mosquito Abatement District notes that ticks are becoming active earlier due to climate change. Ticks enter dormancy below 40 degrees, sheltering under leaf litter and snow, and they perish when temperatures drop below 14 degrees. However, recent cold snaps were accompanied by insulating snow, sheltering ticks from freezing temperatures. Warmer February, March, and April temperatures also contributed to early tick emergence.

The Northwest Mosquito Abatement District observed a nearly sevenfold rise in deer tick sightings this spring. Irwin mentioned that his team is conducting more ‘tick drags’ in suburban areas to collect samples.

Early Tick Bites and Case Study

Ann Miller, a social worker from Jefferson Park, found a tick on her dog, Millie, last year, believing it occurred during a visit to her mother’s house in Crystal Lake. Millie tested positive for Lyme disease. Although initial tests indicated she did not need antibiotics, Millie later developed active Lyme disease symptoms, including limping and a reluctance to move. After taking doxycycline, a few days saw an improvement.

Miller was aware of ticks but did not anticipate early-season bites. Acknowledging the change, Miller started tick medication earlier than the previous year, illustrating the shift in tick activity.

Understanding Tick Behavior and Preventative Measures

Ticks latch onto hosts via ‘questing,’ where they wait in vegetation with outstretched legs to cling to a passing host. They favor shaded, humid areas like leaf piles and feed on a host’s blood for days, potentially transmitting bacteria such as the cause of Lyme disease. Often unnoticed due to their small size, ticks can be as tiny as a poppy seed.

On average, the Illinois Department of Public Health confirms around 300 Lyme disease cases annually. Many instances go unreported as symptoms can mimic the flu, and patients may not remember a tick bite. The IDPH notes a long-term rise in tick-borne diseases, aligning with CDC reports of ‘higher than normal’ emergency room visits for tick bites this April.

Nationally, except for specific states, emergency-room visit rates for tick bites reached their highest since 2017.

Residents like Laura Sislow from St. Charles have experienced the long-term impact of Lyme disease, such as prolonged fatigue that disrupted her life and career. The CDC notes that the cause of persistent symptoms remains unknown.

Public Health Advice and Protection Tips

Healthcare professionals emphasize prevention to combat tick bites. Dr. Ihab Ahmed of Northwestern Medicine urges wearing protective clothing, using repellents, and performing checks after going outdoors. Dressing in light-colored clothing, tucking pants into socks, and using tape can offer protection. Though unfashionable, these measures can help avoid tick bites, reducing the risk of illness.