Howitt1 and her associates of the United States Public Health Service, Atlanta, Ga., report the isolation of encephalomyelitis virus from the blood of nestling wild birds in Colorado. Nestlings from over 600 nests were tested. Birds studied included pigeons, swallows, sparrows, magpies, and blackbirds. On three occasions, intracerebral inoculations of 0.02 cc. of heart blood from these nestlings into 12 to 14-day-old white mice produced symptoms of encephalitis or death in two to five days. The causative agent was fully identified as western equine encephalomyelitis virus.
The Atlanta epidemiologists also tested 78 lots of mites found in the nests of these birds.2 The virus of western equine encephalomyelitis was obtained from one lot only. The virus-positive mites were taken from the nest of an English sparrow, on a farm where a human case of encephalitis had recently occurred. Antibodies neutralizing western equine encephalomyelitis virus were demonstrated in the
ENCEPHALOMYELITIS VIRUS IN WILD BIRDS. JAMA. 1951;147(9):876. doi:10.1001/jama.1951.03670260078021