ABSTRACT
Enterocytozoon bieneusi was originally only reported in humans, both immunocompromised and immunocompetent patients. However, a recent genome survey of E. bieneusi revealed that the organism has a highly unusual and reduced biochemistry. The lack of an animal model and in vitro culture methods limits the investigation of immunology, pathophysiology, and development of treatments for E. bieneusi. Cell-mediated host immune responses seem to be key in defense against E. bieneusi. However, many vertebrate animal hosts have now been shown to harbor E. bieneusi. A report of E. bieneusi in the respiratory tract also suggests the possibility of airborne transmission. E. bieneusi spores also have been identified on other fresh food products and in milk. The chapter describes the several techniques for detection of E. bieneusi: light microscopy, transmission electron microscopy (TEM), immunofluorescence, in vitro culture and animal models and nucleic-acid-based detection.
