Distribution of Cryptosporidium and Cyclospora at Different Depths in Underground Water in the Centre Region, Cameroun: Role of Hydrodynamical Variable

Abstract

This study, developed in Centre Region of Cameroon, made it possible to indicate the consequences responsible of soil vulnerability. Chemical and biological analysis of soil samples collected near wells and springs during the short rainy season were carried out. The results show that the pH and electrical conductivity values decrease with the depth respectively 6.11 CU and 127.47 µS/cm at the surface (0cm) follow by 5.52 CU and 69.32 µS/cm at 50 cm depth. The hydraulic conductivity shows that the soil is moderately permeable (10-5m/s). Protozoa oocysts were observed using an Olympus CK2 inverted microscopy at 40X objective using Zinc sulphate flotation and modified Ziehl-Neelsen technique. The oocysts were counted using a proposal formula. The distribution of oocysts decreases with depth. At the surface of the soil (0cm) the densities of Cryptosporidium and Cyclospora are respectively 123 oocysts/100g and 50 oocysts/100g. At 25cm depth, the densities of Cryptosporidium and Cyclospora are respectively 36 oocysts /100g and 6 oocysts /100g. At 50cm depth the densities of Cryptosporidium and Cyclospora are respectively 16 oocysts/100g and 3 oocysts/100g. The contamination of these different depth layers would be a risk of contamination of groundwater.