Occurrence ofCryptosporidiumandGiardiain irrigation water and its impact on the fresh produce industry

Abstract

In Mexico, relatively few studies have examined the presence of protozoan parasites from surface waters with irrigation and wash-water applications in the fresh produce industry. In this study, the presence of Cryptosporidium oocysts and Giardia cysts in surface water for irrigation, washing and disinfecting applications was evaluated. In addition, the occurrence of Cryptosporidium oocysts and Giardia cysts was determined in wash-water tanks at selected packinghouses. The occurrence of both Cryptosporidium and Giardia was determined by an immunofluorescent technique. Forty-eight percent of the surface water samples tested positive for Cryptosporidium oocysts and 50% tested positive for Giardia cysts. Concentration ranges for Cryptosporidium oocysts and Giardia cysts were 17-200 and 17-1633 per 100 litres, respectively. Sixteen percent of the wash-water tanks tested positive for Cryptosporidium oocysts and 83% were positive for Giardia cysts with concentrations ranging from 1-133 oocysts and 100-533 cysts per 100 litres, respectively. The presence of protozoan parasites in surface water for irrigation and packinghouse operations suggests that there may be a risk of contamination of fresh produce as protozoan oocysts/cysts might come in contact with and attach to crop surfaces posing a risk of infection to consumers who eat these products.

Physicochemical Quality and Chemical Safety of Chlorine as a Reconditioning Agent and Wash Water Disinfectant for Fresh-Cut Lettuce Washing

“…Although there have been large fluctuations in inactivation of norovirus with free chlorine in various studies (dependent on the type of detection, if the viruses are aggregated or dispersed, and if free or total chlorine is measured), concentration ϫ contact times from studies with free chlorine in loworganic-loaded waters show that norovirus and its more practical surrogate murine norovirus are both highly vulnerable to chlorination (31,68,69). Protozoan parasites, such as Cryptosporidium parvum and Cyclospora cayetanensis, have also been associated with outbreaks related to fresh produce consumption, and countries in Latin America have recognized them as pathogens of concern (4,67,70,71). If produce wash water should be kept free of these pathogens, a chlorination system would fail due to the high level of resistance to chlorine (72,73), or alternatively, excessively Van Haute et al high free chlorine concentrations would be required.…”

Development of a Method for Detection of Giardia duodenalis Cysts on Lettuce and for Simultaneous Analysis of Salad Products for the Presence of Giardia Cysts and Cryptosporidium Oocysts

“…Fresh produce, in particular, as it is consumed with minimal preparation, is a potential vehicle of transmission, and G. duodenalis cysts have been detected on produce in several countries (1,12,13,14). Contaminated irrigation water, especially, appears to constitute a major route of contamination of fresh produce (3,21). Practical and reliable detection methods for monitoring foodstuffs will aid the prevention of parasitic disease outbreaks associated with contaminated food (8).…”

Larvas de Strongyloides spp. en lechugas obtenidas en mercados de Lima

“…El agua de riego contaminada, en particular, constituye una vía importante de contaminación para los productos frescos (2) . La lechuga, de elevada demanda de consumo por nuestra población, es susceptible de contaminación, ya que es producida, cosechada y transportada, por lo general, artesanalmente.…”