Identification of an antigenic subtype of eastern equine encephalitis virus isolated from a human.

Eastern equine encephalitis (EEE) virus was isolated from the cerebrospinal fluid of a 6-year-old male who had clinically diagnosed aseptic meningitis and subsequently died. Several standard serologic tests that use polyclonal antibody and indirect immunofluorescence and hemagglutination inhibition tests that use monoclonal antibody provided evidence that the isolate was an antigenic subtype of prototype North American EEE virus. We believe that this is the first evidence of an antigenic subtype of EEE virus.