Microsporidiosis: Enterocytozoon bieneusi in domesticated and wild animals

Authors: Santin-Duran, Monica; Fayer, Ronald

Submitted to: Research in Veterinary Science
Publication Type: Review Article
Publication Acceptance Date: 7/19/2010
Publication Date: 6/13/2011
Citation: Santin, M., Fayer, R. 2010. Microsporidiosis: Enterocytozoon bieneusi in domesticated and wild animals. Research in Veterinary Science. 90(1):363-371.

Interpretive Summary: Microsporidia are microscopic fungi that infect all major animal groups from invertebrates to fish to birds and mammals, including domesticated animals and humans. Enterocytozoon bieneusi is the most commonly reported species of microsporidia in humans. It has also been reported worldwide in animals of veterinary importance including cats, dogs, horses, cattle and pigs). Identification of E. bieneusi in these animals brings into question the possible role of animal reservoirs in the epidemiology of this pathogen. Within the species E. bieneusi, considerable genetic diversity has been found. Based on differences found in the sequence of the ITS region of its ribosomal DNA, over 90 genetically distinct types (genotypes) of E. bieneusi have been identified from spores recovered from the feces of infected humans and animals. Some E. bieneusi genotypes appear to have a narrow host range and others appear potentially zoonotic with the ability to infect many animals including humans. Information presented in this report includes the taxonomy, epidemiology, zoonotic potential, and importance in public health of E. bieneusi.

Technical Abstract: Microsporidia are a ubiquitous group of obligate intracellular parasites that infect all major animal groups. Enterocytozoon bieneusi is the most commonly identified microsporidia in humans and has also been reported worldwide in animals with importance in veterinary medicine (e.g. cats, dogs, horses, cattle and pigs). The identification of E. bieneusi in animals has raised the question of the importance of animal reservoirs in the epidemiology of this pathogen, and the implications of the infection with this pathogen in infected animals. Considerable genetic diversity within E. bieneusi has been found with over 90 genotypes identified based on the ITS nucleotide sequence of E. bieneusi spores recovered from the feces of infected humans and animals. Both host-adapted E. bieneusi genotypes with narrow host ranges and potentially zoonotic genotypes with wide host specificity have been identified. The information presented in this review should be useful in understanding the taxonomy, epidemiology, zoonotic potential, and importance in public health of E. bieneusi.