Identification of Giardia duodenalis in environmental and animal samples in Scotland with development of novel approaches of filtration elution

Abstract

Giardia duodenalis is a waterborne flagellated protozoan parasite known to cause substantial cases of disease throughout the world. The parasite is argued to be zoonotic, and as such consumption of water contaminated by animal faeces containing parasite cysts is thought to lead to human infection. Infection is skewed towards the developing world, but outbreaks do occur within the developed world. This project had two aims: to identify the prevalence of G. duodenalis within a range of Scottish samples, both faecal and water, and to develop a novel method for the elution of G. duodenalis cysts from filter matrixes by incorporating megasonic sonication into a pre-existing method – the FiltaMax system. Molecular techniques found that water samples within this study were mostly negative for parasite DNA, however faecal samples were often positive, with animal samples testing sporadically positive throughout the study. A novel methodology for filter matrix elution of G. duodenalis cysts was developed and proven to be comparable to current leading filtration methods. This megasonic method also boasted significant advantages over the FiltaMax system: such as reduction in labour involved, substantially reduced damage of the parasite during elution and future automation is a possibility.