الفهرس 
Waterborne diseases and etiologic agentsOnly 14 pages are availabe for public view
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Abstract
Unsafe water and poor sanitation and hygiene have been reported to rank
the third among the twenty leading risk factors in the developing countries,
including Egypt. Giardia and Cryptosporidium spp. are protozoan parasites
that cause widespread gastrointestinal illness. Ninety percent of reported
outbreaks of these pathogenic protozoa occur through water, while only ten
percent are related to food. These protozoa have become ubiquitous in surface
water worldwide. The number and the extent of waterborne outbreaks diseases
in the developed countries shows that transmission of Giardia and
Cryptosporidium by drinking water is a significant risk (Baldursson and
Karanis, 2011).
The detection of Cryptosporidium and Giardia (oo)cysts in water includes
conventional staining techniques, immunofluorescent stains and ELISA. They
are time-consuming and require a large number of (oo)cysts and experienced
parasitologists to accurately identify them, so their recovery rates is always
variable. Furthermore, viability of these protozoa can be detected by several
techniques such as staining methods, excystation, animal infectivity and
molecular methods which are still under trial. The (oo)cysts concentrations in
both treated and untreated source water are usually low. Therefore, (oo)cysts
detection methods must be able to identify low concentrations, accurately
count their numbers and determine their viability. Flow cytometry was used in
environmental samples to facilitate the step of detection of Cryptosporidium
and Giardia. In Egypt, no routine work is being done to detect these protozoa
in water and most of the previous studies have involved diagnosis through.