ABSTRACT
The order Microsporidia contains a number of ubiquitous pathogens that can infect various animals, including humans. Enterocytozoon bieneusi and Encephalitozoon intestinalis have been associated with gastrointestinal illness in humans. The effect of four disinfectants--ammonium hydroxide, hydrogen peroxide, and two commercial disinfectants containing peroxyacetic acid (Tsunami) and N-alkyl dimethyl benzyl ammonium chloride (Timsen)--on E. intestinalis spores was examined using exposure times of 1, 5, and 15 min. Spore viability was determined in vitro with RK-13 cells. Hydrogen peroxide was most efficient at inactivating microsporidial spores at all tested concentrations and treatment times, whereas ammonium hydroxide was effective only at the highest concentration at all exposure times. Tsunami (40 microg/ml) and Timsen (200 and 400 ppm) could inactivate spores when incubated for 5 and 15 min.
