[Comparative studies on the significance of the "cornea test" in the diagnosis of rabies].

Foxes that were positive by the fluorescent antibody test on brain were also positive by the corneal test. The corneal test gave a false-negative results only when the specimen was in a macerated state. Out of 133 foxes in which rabies virus was demonstrated in the optic nerve by animal inoculation, only one was negative to the corneal test - this may have been a case of centripetal spread of the infection which was examined at a stage when virus was present in the optic nerve but not in the cornea or the brain. Hence it is possible that the virus may be absent from the cornea. False-positive results seem unlikely to occur, for only one fox was negative upon inoculation of animals with optic nerve and vitreous humour, while the fluorescent antibody test of corneal cells was positive. Animal tests revealed virus inhibitors in the vitreous humour of this animal. All the other cornea-test positive foxes were also positive in tests on brain, lacrimal gland and optic nerve.