The Utah County Health Department said the newest case involves the neuroinvasive disease, the more serious form of the West Nile illness.
According to the U.S. Centers for Disease Control, 11 other human cases have been reported in Utah this year in Box Elder, Cache, Davis, Salt Lake and Weber counties. Seven of those cases were neuroinvasive.
Most people infected with the virus do not develop symptoms. About one in five develop a fever or other symptoms including a headache, body aches, joint pain, vomiting, diarrhea or a rash.
Less than 1% of those infected develop neuroinvasive diseases, such as meningitis or encephalitis, which may require hospitalization.
Health officials say mosquitoes that carry West Nile Virus are most active during dawn and dusk. Residents can reduce the risk of bites by using insect repellent containing DEET, picaridin or lemon eucalyptus oil.
Officials also advise wearing long sleeves and pants and making sure window and door screens are intact to keep mosquitos outside.
