The Illinois Department of Public Health confirmed Wednesday a McHenry County woman in her 50s is the first human West Nile virus case in the state this year.
According to a news release, the McHenry County Health Department reported that the woman became ill from the virus earlier this month.
In 2012, the Illinois Department of Public Health reported 290 human cases of the virus and 12 deaths. It was the second-highest number of human West Nile cases in state history.
A Cook County mosquito sample collected in May was the first to test positive this year. Since then, there have been reports of birds and mosquitoes testing positive for West Nile virus in 50 counties throughout the state.
Common West Nile virus symptoms include fever, nausea, headache and muscle aches that may last anywhere from a few days to a few weeks, although four out of five infected people will not show symptoms.
People older than 50 are at a higher risk for developing severe illnesses, such as meningitis or encephalitis, from the virus.
Precautions against the West Nile virus include reducing exposure to mosquitoes, wearing repellent and reporting dead birds or areas of stagnant water.