Batch solar disinfection inactivates oocysts of Cryptosporidium parvum and cysts of Giardia muris in drinking water

Autor: J. A. Castro-Hermida, Elvira Ares-Mazás, S. Ramalingham, E.A. Meyer, Fernando Méndez-Hermida, Kevin G. McGuigan, C. Sichel, S.C. Kehoe, M.A. Boyle, Pilar Fernández-Ibáñez, B.P. Meyer
Rok vydání: 2006
Předmět:
Zdroj: Journal of Applied Microbiology. 101:453-463
ISSN: 1365-2672
1364-5072
DOI: 10.1111/j.1365-2672.2006.02935.x
Popis: Aim: To determine whether batch solar disinfection (SODIS) can be used to inactivate oocysts of Cryptosporidium parvum and cysts of Giardia muris in experimentally contaminated water. Methods and Results: Suspensions of oocysts and cysts were exposed to simulated global solar irradiation of 830 W m−2 for different exposure times at a constant temperature of 40°C. Infectivity tests were carried out using CD-1 suckling mice in the Cryptosporidium experiments and newly weaned CD-1 mice in the Giardia experiments. Exposure times of ≥10 h (total optical dose c. 30 kJ) rendered C. parvum oocysts noninfective. Giardia muris cysts were rendered completely noninfective within 4 h (total optical dose >12 kJ). Scanning electron microscopy and viability (4′,6-diamidino-2-phenylindole/propidium iodide fluorogenic dyes and excystation) studies on oocysts of C. parvum suggest that inactivation is caused by damage to the oocyst wall. Conclusions: Results show that cysts of G. muris and oocysts of C. parvum are rendered completely noninfective after batch SODIS exposures of 4 and 10 h (respectively) and is also likely to be effective against waterborne cysts of Giardia lamblia. Significance and Impact of the Study: These results demonstrate that SODIS is an appropriate household water treatment technology for use as an emergency intervention in aftermath of natural or man-made disasters against not only bacterial but also protozoan pathogens.
Databáze: OpenAIRE
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