Cryptosporidium Oocysts and Giardia Cysts on Salad Products Irrigated with Contaminated Water

Abstract

A field study in Valencia, Spain, was done to determine the occurrence of Giardia and Cryptosporidium on salad products that are frequently eaten raw, such as lettuces and Chinese cabbage, and in irrigation waters. Four water samples were taken weekly 1 month before harvesting the vegetables. All water samples were analyzed using techniques included in the U.S. Environmental Protection Agency Method 1623. Standard methods for detecting protozoan parasites on salad vegetables are not available. Published techniques for the isolation of parasites from vegetables generally have low and variable recovery efficiencies. In this study, vegetables were analyzed using a recently reported method for detection of Cryptosporidium oocysts and Giardia cysts on salad products. The waters tested were positive for both Cryptosporidium and Giardia. Of 19 salad products studied, we observed Cryptosporidium in 12 samples and Giardia in 10 samples. Recoveries of the Texas Red-stained Cryptosporidium and Giardia, which were used as internal controls, were 24.5% +/- 3.5% for Cryptosporidium and 16.7% +/- 8.1% for Giardia (n = 8). This study provides data on the occurrence of Cryptosporidium and Giardia in salad products in Spain. The method was useful in the detection of Cryptosporidium oocysts and Giardia cysts on the vegetables tested, and it provides a useful analytical tool for occurrence monitoring.

Contamination by intestinal parasites in vegetables marketed in an area of Jequitinhonha Valley, Minas Gerais, Brazil

“…However, parasitological contamination frequently occurs during the field cultivation of vegetables 8 , mainly due the use of contaminated water sources and organic fertilizers for irrigation and soil fertilization, respectively 9 .…”

Risk Assessment for Giardia in Environmental Samples

“…In drinking water, up to 24 cysts/L have been reported [16]; 87 cysts/L in soil; 0.0087 cysts/L in air [17]; and 40 cysts/L in leafy vegetables [18]. Most research has monitored Giardia cysts in water ( Table 2).…”

Neonatal Rat; A Suitable Animal Model for Experimental Cryptosporidiosis

“…In the developing countries, a major obstacle for disease control is the lack of effective methods to curb cryptosporidiosis and reduce environmental contamination with oocysts (9). Cryptosporidium parvum can be spread via food handlers, contaminated foods, fruits, vegetables, and unpasteurized cow milk (10)(11)(12)(13). The epidemiology of C. parvum is investigated in Iran.…”