[Biology, epidemiology and diagnostics of pathogenic waterborne protozoan parasites]

Abstract

Cryptosporidium, Giardia intestinalis, Cyclospora cayetanensis, Isosopra belli and micropsoridia are the most important and common pathogens found in humans and many other species of vertebrates. In humans, mainly in immunocompromised patients, children, pregnant women and elderly people, they are the most frequently identified protozoan parasites causing gastrointestinal disease worldwide. These pathogens have several transmission routes, including anthroponotic and zoonotic transmission. What is more, in many cases of epidemics caused by mentioned pathogens the major cause of infection was contaminated with these organisms water and food. In spite of many existing regulations of clearing and making use of drinking water supplies and recreational water, cosmopolitan protozoan parasites are still the danger of public health. These organisms are responsible for many waterborne outbreaks worldwide. Light microscopy and immunofluorescence assay have been used to identify these organisms in most laboratories. However, these traditional techniques have major limitations in the specific diagnosis, these methods are not sensitive enough to detect cysts or oocysts in environmental samples, so the new molecular tools must be applied. Recently, PCR-based techniques have been developed for detection and genetic characterization of the different species and population variants of protozoan parasites is central to the prevention, surveillance and control of gastrointestinal diseases. In this review were characterized biology, epidemiology and the progress in technology for detection and surveillance of the most important waterborne protozoan parasites.