IMMUNOLOGICAL, MICROSCOPIC, AND MOLECULAR EVIDENCE OF ENCEPHALITOZOON-INTESTINALIS (SEPTATA-INTESTINALIS) INFECTION IN MAMMALS OTHER THAN HUMANS

Encephalitozoon intestinalis (Septata intestinalis) is the second most prevalent microsporidian species infecting humans, but it has not bee n described in other animal species. This investigation examined 10 do mestic animal stool samples (8 mammalian, 2 avian) containing spores d etected by anti-Encephalitozoon monoclonal antibody immunofluorescence (FA). The presence of E. intestinalis but not Encephalitozoon hellem or Encephalitozoon cuniculi was confirmed in 6 of 8 mammalian stool sa mp:ies by species-specific FA and polymerase chain reaction, Clusters of spores inside epithelial cells were observed in feces of five mamma ls (donkey, dog, pig, cow, and goat) using ''quick-hot'' Gram-chromotr ope stain. None of the 10 samples reacted with anti-E. hellem or anti- E. cuniculi sera, nor were they amplified with species-specific primer s for E. hellem and E, cuniculi. To our knowledge, this is the first i dentification of E. intestinalis in animals other than humans. The dat a shown herein suggest the possibility that E. intestinalis infection may be zoonotic in origin.