Encephalitozoon cuniculi spores in blood vessels in the brain of white New Zealand rabbits.

Encephalitozoon cuniculi is a zoonotic mycotic pathogen that infects rabbits. When the host becomes infected, spores in the brain parenchyma cause severe granulomatous meningoencephalitis. The mechanisms by which spores reach the CNS are poorly understood. We divided 27 white New Zealand rabbits into 2 groups: 15 infected orally with 10(6) spores and 12 uninfected controls. Animals were euthanized at 30 d post-infection (dpi). Histologically, spores were present within brain blood vessels at 30 dpi. To our knowledge, the localization of free E. cuniculi spores has not been demonstrated previously within blood vessels in the brain of rabbits.