According to the Iowa Department of Public Health, three cases of the West Nile virus have been reported in Iowa so far this year. The mosquito-borne virus has appeared in the state during early autumn since 2002.
So far, one human case has been reported in each of three counties: Clay, Monona, and Woodbury. The State Hygienic Laboratory, which also tests mosquitos, reports that one mosquito pool has tested positive for the virus.
Symptoms of the virus may include fever, aches and vomiting. More serious symptoms, including brain swelling, affect less than one percent of infected people.
Officials encourage Iowans to use insect repellent when outdoors, especially during evenings, and to avoid standing water.