Diseases that can be Transmitted by Mosquitoes

While mosquito-transmitted disease is not as common in Minnesota as it is in tropical climates, there are several diseases of potential concern to Minnesota residents. Minnesota residents who travel to other countries can return with tropical diseases such as malaria. West Nile virus was found in Minnesota in 2002 and we suspect that this virus will continue to be a public health concern in future years.

  • West Nile Virus (WNV)
    West Nile virus is a disease transmitted to people, horses, and birds. It is the most commonly reported mosquito-transmitted disease in Minnesota. Most people infected with West Nile virus show no symptoms or flu-like symptoms, but some (primarily elderly) have more severe illness.

  • La Crosse Encephalitis (LAC)
    La Crosse encephalitis, which is transmitted by the Tree Hole mosquito, is responsible for 3 to 13 cases of severe illness (primarily in children) each year in Minnesota.

  • Western Equine Encephalitis (WEE)
    During 1941, there was a large regional outbreak of Western equine encephalitis. There may have been as many as 791 cases in Minnesota that year with 90 deaths. In more recent years, Minnesota has had infrequent and smaller outbreaks of WEE (15 human cases in 1975, single cases in 1983 and 1999).

  • Eastern Equine Encephalitis (EEE)
    Eastern equine encephalitis is a rare illness in humans, and only a few cases are reported in the United States each year. EEE is quite severe and typically fatal among infected horses.

  • St. Louis Encephalitis (SLE)
    CDC; Cases of St. Louis encephalitis are usually the result of unpredictable and intermittent localized epidemics. Attention: Non-MDH link

  • Malaria
    CDC; Malaria is not a public health concern in North America, but people who travel to or have lived in other areas of the world may be at risk and should be familiar with the symptoms of the disease and the drugs used to prevent infection. Attention: Non-MDH link


Updated Tuesday, 02-Jul-2013 09:41:00 CDT