Lake County health official shares how to stay tick-free: ‘You might want to have those long pants on'
Residents may be enjoying the sun-dappled hiking trails of Lake County this summer, but they should be cautious of one of nature's more annoying - and even dangerous - parasites, the tick.
These bloodsuckers can carry several potentially severe diseases, and shifting species ranges mean Lake County has a growing variety of ticks, said county Health Department Ecological Services Program Coordinator Alana Bartolai.
In Lake County, one of the more prevalent species is the deer tick, also known as the black-legged tick, and it’s a common carrier of the Borrelia bacteria, which causes Lyme disease. According to Bartolai, the Health Department conducts surveillance work, dragging sheets of fabric through tick habitats and then testing the bugs for various pathogens.
About 35% to 45% of those ticks test positive for Lyme disease, she said. While that number is high, it's generally in line with the county’s historical data, although Bartolai noted there's been a slight increase since testing began in 2013.
Lyme disease can manifest in a number of ways, making it harder to diagnose, she said, although symptoms can include lethargy and fever. There's also often a highly-noticeable "bullseye" rash around the bite area, but it’s not a guaranteed symptom, she said.
"It's important for people, if they do feel sick and they go to their primary provider, to mention if they had been spending a lot of time outdoors," Bartolai said. "It can be a little bit hard to diagnose if they're not testing for it, because some of the symptoms can be all over the place."
The severity of Lyme disease can vary, although the quicker it’s identified, the better, she said. It can even spread to other parts of the body, impacting the nervous system, joints, and the heart. Late-stage Lyme disease can be severe, she warned.
Lyme disease is the most common illness caused by ticks, followed by anaplasmosis, which shows up in about 6% of ticks tested, Bartolai said.
Prime tick season is the spring and early summer, and then the fall, she said. Whether hiking or just gardening in the yard, Bartolai said people need to be mindful of ticks. One simple solution is covering up, but she acknowledged that it can be a hard sell in the summer heat.
"I know when it’s hot, not everyone wants to wear long sleeves and long pants, but if you are going into prime tick habitat - like wooded areas with a lot of leaf litter - you might want to have those long pants on," Bartolai said.
There's also a variety of EPA-approved tick repellents, Bartolai said, although she cautioned that some types are not meant for skin contact - instead meant to be sprayed on hiking gear - and some can be toxic to pets under certain conditions.
After being outdoors, she advised doing a tick check to see if there's any wandering or attached ticks, and to pull any attached ticks off with tweezers. The longer they sit feeding, the greater the risks can be, she said.
If someone finds an attached tick, they can go to their doctor if they're concerned to possibly get preemptive antibiotics. However, the CDC recommends waiting for symptoms. Some people will keep removed ticks in plastic bags in the freezer in case they develop symptoms, Bartolai said, to get help from the Health Department with identification, since only certain species carry Lyme disease.
Shifting ranges
The variety of Lake County ticks has begun to shift, as climate change expands the ranges of species in both north and south Illinois. Deer ticks used to be more prevalent in Wisconsin and Minnesota, but they've been moving south, Bartolai said. And the Gulf Coast and Lone Star ticks, usually southern species, are making their way up.
On the state level, scientists and researchers are warning Illinois' tick season is starting earlier, lasting longer and creeping into new corners of the state.
Milder winters and earlier springs are helping ticks survive in greater numbers, while doctors report earlier cases of tick-borne illnesses this year than in previous seasons. And ticks aren't only in heavily forested areas. More and more, experts say, ticks are also being found in city parks, green spaces and suburban yards.
"It's not true that ticks are only something you're going to encounter on a camping trip. Increasingly, that's simply not true. Ticks don't recognize city limits," said Dr. Kelly Cairns, president of the Chicago Veterinary Medical Association.
Tick season usually spans April through September. But all four seasons have seen warmer temperatures because of human-driven climate change, and winter temperatures have increased at a much faster rate than all other seasons, experts say.
Shorter winters have led to the expansion of tick populations, a trend that is most prevalent in the Midwest and Northeast.
"With climate change, it seems like ticks are able to survive better and get active earlier than what we would usually see," said Patrick Irwin, lead entomologist with the Northwest Mosquito Abatement District, a government agency that monitors and controls mosquito, fly and tick populations in northwest Cook County.
Ticks go dormant in temperatures below 40 degrees, hibernating beneath leaf litter and snow. They begin to die off when temperatures drop below 14 degrees. This year's cold snaps, Irwin said, were accompanied by snow, which insulated the ticks from the full effects of the cold.
February, March and April were also above average in temperature, allowing ticks to emerge from hibernation earlier.
This spring, the Northwest Mosquito Abatement District recorded a nearly sevenfold increase in deer tick sightings compared with last year, Irwin said.
Evgenia Anastasakos of the Chicago Tribune contributed to this report.
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