THE ATTENUATION OF THE VIRUS OF EPIZOOTIC HEMORRHAGIC DISEASE OF DEER BY ITS SERIAL PASSAGE IN THE BRAINS OF NEWBORN MICE.

Serial passage through the brains of newborn mice markedly attenuates the New Jersey strain of EHD virus. Deer inoculated with this attenuated virus show no clinical evidence of illness, but do develop virus-neutralizing antibodies in their sera. They also become solidly immune to infection with the regularly fatal unattenuated virus.