The Illinois Department of Public Health is reminding Illinoisans that warmer weather isn't just a signal for more time outside, it also brings a higher risk of illnesses carried by animals and biting pests.

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As tempts rise as we near summer, the IDPH is urging residents to take simple but important precautions while enjoying the outdoors, especially as certain diseases start to show up again across the state.

Illinois DPH Issues Warning About Animal & Pest-Borne Illnesses

This year, officials are focused on three main concerns: ticks, mosquitoes, and bats.  The first positive batches for West Nile have been detected in Cook County already, but no human cases have been reported this year.

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West Nile is most commonly spread through the bit of a house mosquito that had first fed on an infected bird.  For many people, symptoms may be mild or even nonexistent.  When symptoms do appear, they can include fever, headache, nausea, and muscle aches that may last anywhere from a few days to several weeks.  In more severe cases, the illness can escalate into dangerous conditions like meningitis, paralysis, or even death.

The IDPH says that older adults, especially over 60, and individuals with weakened immune systems are at highest risk for severe complications.

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Health officials also continue to monitor bats and rodents due to the risk of other rare but serious illnesses.  While less common, concerns like hantavirus remain relevant in discussions about animal-born diseases, particularly in rural or enclosed spaces where exposure to droppings can occur.  Though cases are rare, hantavirus can cause serious respiratory illness and is another reminder that pest exposure should not be taken lightly.

As summer approaches, the message from public health officials is simple: enjoy the outdoors, but stay aware, stay protected, and take steps to reduce exposure to biting insects and wildlife.