RESUMO
Examinations were carried out on the occurrence of active virus, antigen and antibodies in the brain blood, or resp. of rabbits which were infected intracerebrally with the virus of Borna disease as a model of slow viruses. The techniques of the complement fixation and the immunofluorescence were used. Furthermore, an attempt was made to demonstrate interferon in the blood serum of the infected rabbits. Virulent Boran virus was observed two days after the infection and complement fixing antigen from the 10th day on. The immunofluorescence technique gave positive results in the nucleus of ganglion cells eight days after infection. The production of interferon in the sera could not be demonstrated. The brains tested 2, 4, 8, and 20 days after infection were also negative.