Investigating the Occurrence of Soil-Transmitted Parasites Contaminating Soil, Vegetables, and Green Fodder in the East of Nile Delta, Egypt

Abstract

Background. Food-borne parasites are major sources of human and animal illness, posing severe health risks in places with contaminated soil, poor water quality, cleanliness, and poor sanitation. The usage of untreated organic fertilizers arising from the excreta of the parasites’ definitive hosts either man or animal pollutes the agricultural soil and is reflected in its products of vegetables and green fodders causing serious health problems. Therefore, to the best of our knowledge, this will be the first study that investigated the combination of parasitic contamination of the agricultural soil and its products of raw eaten vegetables and green fodder in East Nile Delta, Egypt. Aim. The purpose of this study was to investigate the type and degree of contamination caused by parasites in regularly used raw vegetables, green fodder, and soil samples collected from open fields in Egypt’s East Nile Delta. Study Procedures. A cross-sectional study comprised a simple random collection of 400 soil samples, 180 green fodder samples, and as well as 400 vegetable samples, including lettuce, radish, coriander, parsley, dill, watercress, tomatoes, green pepper, cucumber, and carrot, that were gathered throughout one year period from January to December 2021 to represent all seasons (winter, spring, summer, and autumn). The research locations were chosen from various open green fields and farming regions in Egypt’s East Nile Delta producing ready-to-eat vegetables for human consumptions and planting green fodder for animal feeding. Concentrations, including sedimentation, and flotation, and staining techniques were used to recover the greatest number of parasitic life forms. The parasitic structures discovered were identified using biometric and imaging data and compared with known parasite morphology. Statistical analysis was performed with the SPSS software version 22 (IBM, Chicago, IL, USA). Data were presented in numbers and percentages. P -values equal to or less than 0.05 were considered to be statistically significant. The difference in parasitic contamination among the different categories was compared using the chi-square test. Results. In this investigation, 243 out of 400 soil samples (60.7%) confirmed positive for parasitic contamination ( P < 0.05 ). Various parasitic life forms were significantly found in 249 out of 400 (62.25%) of the vegetable samples, with (65.1%) of them harboring one parasite species, whereas 9.2% significantly contained up to three parasites. Ascaris eggs, Trichuris eggs, and Giardia cysts were the most prevalent parasites, which were predominantly isolated from vegetables with uneven surfaces. 109 of 180 (60.0%) green fodder samples confirmed insignificantly positive for parasitic pollution. The proportion of parasite contamination in vegetable samples was insignificant although the highest was in spring (29.3%), followed by summer (27.7%), whereas it is significant in autumn (24.5%). The prevalence rate was the lowest in winter (20.1%). Conclusion and Recommendations. Our findings demonstrated a significant load of parasites notably the soil-transmitted parasitic infection in raw vegetables and green fodder cultivated in open fields as well as in their mother soil in the east of the Nile Delta, Egypt. These results confirm the urgent need to deploy strict control measures to the soil, especially during the pre-harvest period of raw eaten vegetables and green fodder, a critical step in reducing food-borne transmission of soil-transmitted parasites to man and animals.

Field study of parasitic contamination of fruits, vegetables and leafy greens in the Ecuadorian Andes

“…Noteworthy, onions (54.9%), carrots (13.2%) and radishes (24.6%) are frequently consumed raw and can function as efficient vehicles for parasites. Evidence of these tubers exhibit significant rates of parasitic contamination has been previously reported elsewhere ( Puig-Peña et al 2013 ; Yahia et al 2023 ).…”

“…and Giardia duodenalis , Toxoplasma gondii , Entamoeba histolytica , Blastocystis sp., Cystoisospora belli , Balantidium coli , Dientamoeba fragilis , Echinococcus sp., Dipylidium caninum , Ascaris sp., Trichuris sp., and Nematode spp. Larvae ( Dixon, 2016 ; Caradonna et al, 2017 ; Karshima, 2018 ; Robertson, 2018 ; Barlaam et al, 2021 ; Yahia et al, 2023 ).…”

Prevalence and Distribution of Geo-Helminths and Intestinal Protozoa Infections among School-Going Children in Nyeri County, Kenya

“…The fact that mud soil offers adequate moisture and little sunlight. The tightly adhering particles prevent parasitic larvae from moving to deeper soil layers, allowing most parasites to survive for a long time, supporting this conclusion (Yahia et al, 2023).…”

Parasitological contamination of arable soil in selected regions of Poland – preliminary study

“…sandboxes and city parks [16,17,[32][33][34][35][36], as well as from school premises (including rooms used as classrooms) [37,38]. Subsequently, these include, for example, soil collected from farm animal farms and their immediate vicinity [24,39,40], from gardens and fields fertilized with sewage, and from where plants intended for direct consumption (vegetables and fruits) are cultivated [9,24,41]. There are very few articles describing research conducted on specific agricultural fields, e.g.…”

“…Research by many authors indicates differences in the occurrence of parasite eggs in the soil depending on the period of sampling. However, most of them found a more frequent occurrence of eggs in spring and summer [21,41,43]. The more frequent occurrence of parasite eggs in samples taken in autumn can be explained by the timing of fertilizing fields with natural fertilizers, where many farmers prefer fertilization in late summer and autumn (i.e.…”