# Food and Drinking Water as Sources of Pathogenic Protozoans: An Update
## 9 Cyclospora cayetanensis
### Dietary Sources of C. cayetanensis  
Contamination of fruits by _C. cayetanensis_ was recently observed in imported blueberries in Italy; in Norway for 8.7%, 5.5%, and 4.8% of imported and locally produced raspberry, blueberry, and strawberry, respectively; and in central Mexico for 16.6% and 27.3% of blueberries and blackberries from commercial farms, respectively; and in one strawberry sample among 120 analyzed in  
Bogota, Colombia. In a dry area of northwest Mexico _Cyclospora_ spp. was detected in 1.0%, 5.0%, and 30.0% of melon, peach, and grape samples, respectively, with no differences in the percentage of positive samples between those collected in open-air markets or closed markets [38; 237; 247; 248].  
Contamination of leafy greens and other vegetables by _C. cayetanensis_ was detected in 0.3% of samples in the USA and 0.28% in Canada [243; 249]. In Iraq, _C. cayetanensis_ was detected in 3.7% of fresh produce in Baghdad Province and in washing water from at least one sample of garden cress, radish, leek, green onions, and purslane with 6, 7.8, 7.2, 4.4, and 3.2 oocysts per liter, respectively, in Anbar Province. In China, _C. cayetanensis_ was only identified in two vegetable samples, 0.2% of those analyzed, and isolates showed the identity of the 18S ribosomal RNA gene with a _C. cayetanensis_ human isolate from Shanghai. In Mexico, _C. cayetanensis_ was detected in 3% fresh asparagus samples and 3 out of 77 samples of fresh produce collected at local markets in Venezuela. _Cyclospora_ spp. was detected in 3-4% tomato, green pepper, and salad samples and eight types of fruits and vegetables from markets of Dire Dawa City, Ethiopia as well as in 2.9% vegetable samples, including watercess, parsley, radish, and green onion, but not lettuce or coriander, In Egypt, in the El-Kharga Oasis, Upper Egypt, 20% positive samples of arugula and radish were identified in public markets. No _Cyclospora_-positive samples of fresh-cut fruit products were found at retail in Korea by qPCR [237].  
_Cyclospora cayetanensis_ was found to occur in marine crustaceans and mollusks such as bivalve shellfish and wild clams in Tunisia, Egypt, and Turkey; mussels (_Mytitus galloprovincialis_) near the west coast of Turkey; and blue crabs (_Callinetes sapidus_) from Lesina lagoon, Italy, thus showing its occurrence in the marine ecosystem [176; 243].  
_Cyclospora_ spp. in drinking water was reported in a major watershed in the Philippines after rainfalls and in a watershed in Bamenda, Cameroon, among other protozoan parasites, in a concentration of 141.31 \(\pm\) 143.19 oocysts/L in the rainy season and 471.42 \(\pm\) 216.32 oocysts/L in the dry season. In Turkey, _Cyclospora_ was found in agricultural irrigation water samples collected in Denizli City Center but not in drinking water [237].  
In Italy, 30% (3/10) of train tap water samples were positive for _C. cayetanensis_, and in the Apulia region, the parasite was identified in treated wastewater (21.3%), well water (6.2%), soil (11.8%), and vegetables (12.2%) [243].  
The low number of oocysts present makes it difficult to detect _C. cayetanensis_ in fresh produce and environmental samples. Therefore, molecular techniques, including quantitative PCR (qPCR) tests, were recently developed for its detection in these samples and in water to improve outbreak investigation and prevention [243; 250]. The genotyping system based on eight genetic markers applied to human clinical samples was not yet successfully employed for food samples. However, a workflow was recently developed and successfully applied to obtain complete mitochondrial genome sequences from produce samples spiked with low numbers of _C. cayetanensis_[243].