

@article {5215,
	title = {{Effect of various environmental factors on the viability of Cryptosporidium parvum oocysts.}},
	journal = {Journal of Applied Microbiology},
	volume = {104},
	number = {4},
	year = {2008},
	month = {apr},
	pages = {980{\textendash}6},
	abstract = {AIMS: To evaluate individual and combined effects of temperature (4, 18 and 25 degrees C), pH (7 and 10), ammonia (5 and 50 mg l(-1)) and exposure time (1, 2, 4 and 6 days) on the viability of Cryptosporidium parvum oocysts in water. METHODS AND RESULTS: The viability of oocysts was evaluated using the fluorogenic vital dyes assay (4{\textquoteright},6-diamidino-2-phenylindole and propidium iodide). All the factors analysed (temperature, pH, ammonia and exposure time) and their interaction were statistically significant (P {\textless} 0.005). Exposure of oocysts to pH 10 for 6 days at 25 degrees C reduced oocyst viability from approximately 80{\%} to 51{\%}. Similarly, the exposure of C. parvum oocysts to 5 mg NH(3) l(-1) and 50 mg NH(3) l(-1) for 4 days reduced their viability from between approximately 80{\%} to 41.5{\%} and 14.8{\%}, respectively. CONCLUSIONS: The interaction between pH, temperature and exposure time may have adverse effects on the survival of C. parvum oocysts in water. Low concentrations of ammonia, as commonly found in alga-based wastewater systems, over a long period of time can produce high C. parvum oocyst inactivation rates. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides relevant data on the inactivation of C. parvum oocysts in alga-based wastewater-treatment systems in the northwest of Spain.},
	keywords = {Ammonia, Animals, Cell Survival, Cryptosporidium parvum, Cryptosporidium parvum: physiology, Disinfectants, Hydrogen-Ion Concentration, Oocysts, Spain, Temperature, Time, Water Microbiology, Water Purification, Water Purification: methods},
	issn = {1365-2672},
	doi = {10.1111/j.1365-2672.2007.03620.x},
	url = {http://www.ncbi.nlm.nih.gov/pubmed/17973913},
	author = {Reinoso, R. and B{\'e}cares, E. and Smith, H.V.}
}
