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La Crosse encephalitis


Other Names:
Californian encephalitis
Categories:
La Crosse (LAC) encephalitis is a mosquito-borne virus that was first described in La Crosse, Wisconsin in 1963. Since then, it has been reported in several Midwestern and Mid-Atlantic states.[1] The LAC virus is one of many mosquito-transmitted viruses that can cause an inflammation of the brain (encephalitis). About 80-100 cases of this condition are reported each year in the United States.[2] Most cases occur in children younger than age 16. While most people who become infected have no symptoms, those who do become ill may have fever, headache, vomiting and lethargy (tiredness). Severe cases develop encephalitis accompanied by seizures. Coma and paralysis occur in some cases.[1][2] There is no specific treatment for LAC encephalitis. Supportive therapy is provided to those who develop severe cases of the disease.[2]
Last updated: 9/11/2015
Most people infected with LAC encephalitis do not have symptoms. Those that do become ill may initially have fever, headache, vomiting and lethargy (tiredness). Severe cases may develop encephalitis, an inflammation of the brain, which is often accompanied by seizures. Coma and paralysis may also occur. Most cases that develop symptoms occur in children under the age of 16[1][2] Symptoms, if present, typically develop 5 to 15 days after the bite of an infected mosquito. Most cases occur during the summer months.[2]
Last updated: 9/11/2015
There is no specific treatment for LAC encephalitis. Severe cases are treated with supportive therapy which may include hospitalization, respiratory support, IV fluids and prevention of other infections.[2]
Last updated: 9/11/2015

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • You can obtain information on this topic from the Centers for Disease Control and Prevention (CDC). The CDC is recognized as the lead federal agency for developing and applying disease prevention and control, environmental health, and health promotion and education activities designed to improve the health of the people of the United States.

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss La Crosse encephalitis. Click on the link to view a sample search on this topic.

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  1. La Crosse Encephalitis. Virginia Department of Health. March 29, 2013; http://www.vdh.virginia.gov/Epidemiology/DEE/Vectorborne/factsheets/lacrosse.htm. Accessed 9/11/2015.
  2. La Crosse Encephalitis. Centers for Disease Control and Prevention (CDC). October 16, 2009; http://www.cdc.gov/lac/gen/qa.html. Accessed 9/11/2015.