Encephalitozoon infection in birds

Abstract

Encephalitozoon hellem is a single-celled, intracellular parasite of the phylum Microspora. E. hellem was first recognized in immunosuppressed humans where it causes keratoconjunctivitis, sinusitis, and, uncommonly, systemic disease. Increasing evidence strongly suggests that birds are the primary host for E. hellem and that most bird infections are self limiting and do not result in disease. To date, commercially raised lovebirds appear to have the highest prevalence of spore shedding of the birds examined. When disease does occur in birds, it is usually associated with another immunosuppressive infection, inadequate husbandry, or immaturity. The kidney, liver, and intestine are the most common targets of infection, but lesion distribution is variable. Disease has been documented in a wide range of companion birds including parrots and finches, in an ostrich, and in wild hummingbirds. Albendazole has been used for systemic treatment of E. hellem and albendazole in combination with fumagillin have been used to treat ocular manifestations of E. hellem.