Medical Definition of La Crosse encephalitis
: an encephalitis typically affecting children that is caused by the La Crosse virus transmitted especially by a mosquito of the genus Aedes (A. triseriatus)
La Crosse encephalitis, named for the Wisconsin city where it was discovered in the 1960's in a child who died, now occurs widely across the country. It is spread by a late-afternoon biter, Aedes triseriatus, a woodland dweller that breeds in water-filled tree holes and old tires.— Jane E. Brody, The New York Times
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