Prevalence of enteric Protozoa on fresh vegetables and their irrigation water in Giza, Egypt

Abstract

Cryptosporidium spp., Entamoeba histolytica, and microsporidia are the most common enteric protozoans acting as parasitic agents of waterborne diseases. They are considered to be responsible for human infections. Fresh vegetables are one of the most important vehicles of foodborne protozoan parasitic disease transmission. Vegetables are contaminated with enteric Protozoa from the beginning of the planting process to the consumption. In the present study, a total of 110 vegetable samples were collected from agriculture fields (3 regions; two from Nahia and one from Saft Al-Laban, Giza governorate, Egypt). Moreover, 36 irrigation water samples (ground and surface freshwater ) were collected from the same agriculture fields. Another group of 109 vegetable samples was collected from the public markets in Dokki district, Giza governorate, Egypt. Each sample was separately processed and examined for determining the prevalence of enteric Protozoa. The results showed that 39 (35.5%) out of 110 field-collected vegetable samples from three agriculture field areas, 37 (33.9%) out of 109 vegetable samples from markets, and 7 (19.4%) out of 36 irrigation water samples were positive for the three intestinal Protozoa. The most contaminated vegetables were those collected from Nahia 1 area (irrigated with surface water) 41.9%, followed by the Saft area (irrigated with groundwater) 34.8% and Nahia 2 area (irrigated with groundwater) (32.1%). The most contaminated irrigation water was the surface water collected from Nahia 1 area (50%) followed by ground irrigation water in Saft Al- Laban (8.3%). No contamination in groundwater of Nahia 2 area. The most contaminated vegetable was dill collected from both filed and market samples (71.4% and 66.7%, respectively). The most dominant type of enteric parasite was microsporidia spores, on-field vegetables (18.2%), market vegetables (18.3%), irrigation water (11.1%); the last was also contaminated with Cryptosporidium oocysts (11.1%).