The Kansas Department of Health and Environment (KDHE) has issued a high-risk warning for West Nile virus infections (WNV) for north central, south central, northeast and southeast Kansas. Northwest and southwest Kansas are at moderate risk for WNV infections. West Nile virus is the leading cause of mosquito-borne illness in the continental United States. It is most often spread to people through mosquito bites, but it is not spread from person to person. About 1 in 5 people who are infected develop a fever and other symptoms.