La Crosse virus is a type of virus that primarily affects humans and is transmitted by mosquitoes, particularly the Aedes and Culex species. It is most commonly found in the Midwestern United States and can cause a disease known as La Crosse encephalitis, which is an inflammation of the brain. Infection with La Crosse virus often leads to mild symptoms, such as fever and headache, but can sometimes result in more severe neurological issues, especially in children. There is currently no specific treatment for the virus, so prevention focuses on avoiding mosquito bites through the use of repellents and protective clothing.