Abstract
Olfactory receptor neurons are unique in their anatomical structure and function. Each neuron is directly exposed to the external environment at the site of its dendritic nerve terminals where it is exposed to macromolecules. These molecules can be incorporated into by olfactory receptor neurons and transported transsynaptically to the central nervous system. Certain neurotropic pathogens such as herpes simplex virus and Borna disease virus make use of this physiological mechanism to invade the brain. Here the authors review the olfactory transmission of infectious agents and the resulting hazards to human and animal health.
The authors thank Professor K. Asamoto for his helpful advice on neuroanatomy. This work was supported in part by JSPS KAKENHI (15590424). I. Mori is the recipient of an Encouragement of Young Scientist Award (2003) from the Nakanihon Infectious Diseases Research Foundation, Japan.