Arkansas has logged its 16th human case of the West Nile virus. The most recent case was reported in Union County. In all, seven human cases were reported in Jefferson County, two in Pulaski County, and one each in Cleburne, Columbia, Drew, Johnson, Miller, Sevier and Union counties. The mosquito-borne virus has been detected in humans, horses, birds, or mosquito pools in 44 of the state`s 75 counties. Last year, the department reported five deaths in the state among people who contracted the virus. Most people who contract the disease have mild or no symptoms. In rare cases, the illness can cause fatal brain swelling.