This year after having shown a gradual increase in recent years
Chris Stone, director of the Medical Entomology Laboratory at the Illinois Natural History Survey, said Lyme disease has doubled over the last decade.
Stone said there's no way to forecast the increase in disease, which is caused by tick bites, but the trend in recent years gives experts an idea of what should be expected.
"Our expectation would be to further increase the number of Lyme cases," Stone said. "It has been such a gradual increase over the past few years."
Stone said the increase in Lyme disease is not a one-time event appearing out of nowhere like the West Nile or Zika viruses, but there is still reason for concern.
"From a public health concern, that's very important," Stone said. "It's about concern because Lyme can be dramatic or impactful for people who get it."
Lyme disease symptoms include circular red rashes, fever, fatigue, headaches, muscle and joint pains, paralysis, numbness and can lead to death if left untreated, according to the Illinois Department of Public Health.
Stone said the tick species that transmits Lyme has been moving Illinois steadily over the past decade, leading to the gradual increase of Lyme cases in humans.
"It has become much more prevalent," Stone said. "The number of human cases in Illinois has been gradually increasing every year."
He said, "The danger of ticking is that of people who are exposed to natural disasters when they visit or live in natural areas."
"It's often associated with hiking, natural areas and recreation," Stone said.
He added that people who live in their backyard.
"It affects everyone from children to the elderly," Stone said. "Anyone who's outdoors and exposed can pick these up."
The IDPH recommends wearing light-colored protective clothing, applying tick repellent with at 10 percent to 30 percent DEET content on clothes and skin, avoiding brushing against tall grass and checking and checking frequently.