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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.

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