Biodiversity of intestinal parasites in urban waters of the Ouislane River in central Morocco

Abstract

The objective of the present study is to shed light on the parasitic load characterization of wastewater samples collected from four selected stations (O1, O2, O3 and O4 selected from upstream to downstream, on the bed of the Ouislane River in central Morocco. Parasite load flux (quantitative and qualitative) was determined monthly for one year, from January through December 2017, using direct spawning examination, the modified Bailenger concentration technique and the Faust flotation technique. Parasitological examination allowed the identification of helminth eggs and protozoan cysts, on the one hand, and the evaluation of the variation in the concentration of the parasitic load of this wastewater, on the other hand. The results of the present work allow the identification of 17 taxa: Ascaris lumbricoïdes, Trichuris trichiura, Capillaria sp, Ancylostoma diudinal, Enterobius vermicularis, Toxocara canis, Strongyloïdes stercolaris, Hymenolepis nana, Hymenolepis diminuta, Taenia saginata, Fasciola hépatica, Giardia lamblia, Entamoeba coli, Entamoeba histolytica, Blastocystis hominis, Balantidium coli and Cryptosporidium parvum. with a predominance of protozoan cysts over helminths eggs. The evolution of the parasitic load over time indicates the ubiquity of these parasitic species in raw wastewater at variable concentrations, which are closely related to the periods of human activities and according to the seasons. However, the high load of these intestinal parasites in the urban waters of Ouislane wadi will have a potential impact on human and livestock health. Hence the interest to prohibit their use commonly observed in the field and their practice in agriculture.