A Chicago woman was the first person in 2018 to contract a cases of the mosquito-borne West Nile virus in Illinois.
The The Illinois Department of Public Health (IDPH) announced Wednesday that the woman became ill in the middle of May, but additional testing didn’t confirm she was sick with West Nile until Tuesday.
IDPH ordered the testing from the Centers for Disease control and Prevention after the woman became sick a couple months earlier than the typical start of West Nile season, officials said. Illinois’ first case in 2017 was reported on July 20.
“West Nile virus can cause serious illness in some people so it’s important that you take precautions like wearing insect repellent and getting rid of stagnant water around your home,” said IDPH Director Nirav D. Shah.
In 2017, 90 human cases were reported, including eight deaths, the IDPH said, adding that human cases are typically underreported.
Common symptoms of West Nile include fever, nausea, headache and muscle aches, which may last from a few days to a few weeks. Four out of five people infected with the virus won’t show symptoms.
Additional information about West Nile virus can be found on the IDPH website.