Herpetic vestibular neuritis: an experimental study.

An animal model of vestibular neuritis was developed by inoculating herpes simplex virus type 1 (HSV-1) into the auricle of mice. Postural deviation was observed in 5 of 99 mice at 6 to 8 days after inoculation. Following evaluation of the vestibular function, the animals were sacrificed and the vestibular nerves examined for histopathology and immunohistochemically. All mice developed postural deviation, presented as abnormal behaviour; they could not perform various vestibular tasks, such as gait, traversing a narrow path, climbing a rope, negative geotaxis, grasping a rod, and swimming. Degeneration of Scarpa's ganglion was observed in 4 of 5 mice that developed postural deviation, while HSV-1 antigens were found in 2 of them. No such histological findings were seen in animals with normal vestibular function.