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La Crosse Encephalitis

La Crosse encephalitis (LAC) is an arbovirus (arthropod borne virus) transmitted by mosquitoes and was first identified in the early 1960s as an important cause of mosquito-borne encephalitis in children. Most cases of LAC are reported in children age 15 years or younger. LAC is the most common arbovirus reported among West Virginia residents, with approximately 10–20 cases reported per year. Prevention includes taking steps to remove containers that collect water near homes (where mosquitoes lay eggs) and the regular use of mosquito repellants.

Reporting Guidelines


Current Case Definition

Required Forms

General Information

LHD Tools

Surveillance Data

Vectorborne Disease Report Latest 2016 data on mosquito-borne and tickborne diseases in WV.
2015 Zoonotic Disease Report Annual summary report of vectorborne condition surveillance data.
West Virginia Zoonotic Disease Surveillance Summary, 2014 Click at left to view the 2014 surveillance information about mosquito-borne, tickborne, and other reportable zoonotic diseases.

Other Links

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