California encephalitis in Alabama.

Arthropod-borne virus (arbovirus) infections in humans are primarily central nervous system infections, but other clinical manifestations include febrile illness and fever with hemorrhagic diathesis. In the genus Bunyavirus there are several viruses that cause disease in humans, especially in North America; these include LaCrosse, Jamestown Canyon, trivittatus, and snowshoe hare viruses. The disease seen mainly in children is California encephalitis (usually of the LaCrosse subtype); this infection is widespread in the United States but is most prevalent in the upper Midwest, especially in rural areas. We present the first reported case of California encephalitis in rural Alabama; the patient was a 7-year-old boy who came to us with fever and seizures in the summer of 1994. This report stresses the importance of including California encephalitis in the differential diagnosis when children have fever and altered sensorium after exposure to mosquitoes during summer months.