Encephalitozoon cuniculi: An Emergent Pathogen

Encephalitozoon cuniculi is a pathogen with a worldwide distribution, belonging to the phylum Microsporidia (kingdom Fungi), which infects rabbits (Oryctolagus cuniculus) and several other animals, including humans. Encephalitozoon cuniculi was the first microsporidium to be described in mammals. The global population of rabbits is exposed to this pathogen, and, although most infections are subclinical, E. cuniculi can cause severe illness, with neurological, ocular, and renal involvement. In humans, especially in immunocompromised individuals, E. cuniculi has been implicated as an opportunistic agent. Spore proliferation and migration can be reduced by treatment, and preventive antimicrosporidial medications may be considered. Different control measures are necessary for decreasing the spread of E. cuniculi, not only to other rabbits but also to humans. This chapter provides a review of the literature regarding the pathogen E. cuniculi, infection epidemiology, pathogenesis, lesions and clinical signs of disease, and diagnostic and control methods including treatment and prevention of encephalitozoonosis.