The Kentucky Department for Public Health has reported four cases of West Nile virus in Kentucky adults. Kentucky's cases include one in Fayette County, two in Hopkins County, and one in Jefferson County.

Kentucky has seen an average of about 10 cases per year between 2012 and 2016. West Nile is transmitted through mosquito bites. The Kentucky Department for Public Health has worked with local health departments and the Kentucky Department of Agriculture to aid in mosquito control and to monitor the West Nile virus.

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Most people infected with the virus show no symptoms or show only mild symptoms, which include fever, headaches, body aches, diarrhea, vomiting, and rash. Only a very small percentage, less than one percent, will develop neurologic illnesses which produce inflammation of the brain and surrounding tissues. Those with other illnesses, such as cancer or diabetes, or those who are elderly, are at greater risk for serious illness.

The Kentucky Department of Public Health advises avoiding mosquitos, which are more prevalent between dusk and dawn. Residents are advised to use bug spray or wear long sleeves and pants when going outdoors. Inside homes, residents may install screens on windows and doors and empty any standing water inside and around their home.

There are currently no vaccines or medications to treat West Nile virus. Those with mild cases should recover on their own, though symptoms may linger for several weeks. Those with more serious conditions may need to be hospitalized to receive intravenous fluids, pain medication, and nursing care.

West Nile has been discovered in mosquitos around the state and horses in Bourbon, Franklin, Hart, and Russell counties. Though there is no vaccine for people, there is a vaccine for horses.

Surveillance of mosquitos for West Nile is ongoing throughout the state. Trapped mosquitos are tested for the virus, along with Zika and St. Louis encephalitis. There have been no reports of Zika or St. Louis encephalitis.