Abstract of PhD Thesis

Pulsed UV light inactivation of Cryptosporidium parvum and other microbial species in drinking water supplies in Ireland

Mary Garvey, Athlone Institute of Technology (2009)

Cryptosporidium parvum is an enteric coccidian parasite that causes frequent water borne diseases in humans, and is resistant to disinfection with chlorine at concentrations typically applied in drinking water treatment plants. This landmark study investigated critical inter-related factors affecting the use of pulsed UV light (PUV) as a novel alternative means of killing C. parvum and other related microbial pathogens in water. Critical electro-physical and biological factors were identified for optimized destruction of C. parvum in water. Front line methods of measuring disinfection efficacy were used including surrogate vital staining, in vitro HCT-8 cell culture combined with real-time quantitative PCR assay, and the ‘gold standard’ mouse-based infectivity bioassay. In addition to identifying reliable and repeatable operational conditions for the rapid destruction of C. parvum, this study also showed that cell culture is equivalent to the mouse-based infectivity for determining disinfection performances for PUV treatment of oocysts, thus negating the need for use of animals in future disinfection studies.