Health officials have been tooting the precautionary horn after a batch of mosquitoes tested positive for the West Nile virus. In late June, the Will County Health Department announced that a batch of mosquitoes in the city of Joliet, around 40 miles southwest of Chicago, tested positive for West Nile virus.As per the Illinois Department of Public Health data, mosquito-borne illness had already been found in 22 of the state’s counties. Health officials in Chicago issued a similar warning a few weeks earlier, as a batch of mosquitoes there tested positive for the virus.“With mosquito season underway in Illinois, it is now time for Illinoisans, especially seniors and those with weakened immune systems, to start taking precautions to prevent mosquito bites,” said IDPH Director Dr. Sameer Vohra, according to Patch.
Why should you be concerned?

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West Nile virus is an illness that spreads through mosquito bites. It can cause symptoms such as fever, headache, body aches, vomiting, diarrhea, and rash, as per the Centers for Disease Control and Prevention. Along with infections, however, it can also be fatal, as it caused 69 human cases in Illinois in 2024 with 13 deaths, as per IDPH.The virus has been in the U.S. since 1999; however, with the increasing temperatures, mosquitoes are not only increasing in numbers, but also in range, being active for longer seasons and moving into higher altitudes.
What’s being done about the illness?

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The IDPH is encouraging people to “fight the bite” to avoid contracting the virus. Eliminating standing water, using screens on windows or doors and keeping them shut, wearing long clothing and using an Environmental Protection Agency-registered insect repellent when outdoors, are some suggested precautionary measures.There have also been community efforts to reduce mosquito populations. For instance, officials in one Florida county are using X-rays to kill invasive mosquitoes, and a Manila neighbourhood is paying residents to bring in any mosquitoes they can capture.