Abstract
Intranasal inoculation of mice aged 1-6 days with Mount Elgon but virus produced an acute brain infection and death of all the mice at 5-7 days after inoculation. Virus multiple in the olfactory bulbs and spread to the midbrain and then hindbrain, reaching titres of 10(9)-10(1)) plaque forming units/g of wet tissue. Fatal disease was prevented by administration of virus antibody after infection, which was then restricted to the olfactory bulbs. Antibody was about 99% in olfactory bulbs but by only a small fraction in midbrain and hindbrain. The findings may reflect differences in virus maturation and spread, and the accessibility of virus antibody to the olfactory bulbs, midbrain and hindbrain.