Caroline Ajonina
Hamburg University of Technology, Germany
Title: Bioaccumulation of waterborne parasites Entamoeba histolytica, Cryptosporidium spp. and Giardia duodenalis in freshwater bivalvia
Biography
Biography: Caroline Ajonina
Abstract
Although water is considered as one of the best investigated media, waterborne transmission of life-threatening microorganisms still constitutes a serious global health risk. Cryptosporidium spp., Giardia duodenalis, and Entamoeba histolytica are the main causative agents of water associated outbreaks of parasitic protozoan diseases documented worldwide. The pathogens are transmitted inter alia by ingestion of food or water contaminated by their transmissive stages (cysts or oocysts). We investigated the bioaccumulation of parasite stages in mussels downstream of wastewater treatment plants in the Rhine basin, Germany. The aim was to gain an in-depth understanding of the transmission dynamics of the pathogens by examining the links between wastewater discharge and the prevalence and dissemination of the pathogens. Thirty mussels of Dreissena polymorpha and Corbicula fluminea have been tested for the presence of Cryptosporidium spp., G. duodenalis, and E. histolytica using modified Ziehl-Neelsen and Hematoxylin and Eosin (H&E) staining techniques. Cryptosporidium spp. and E. histolytica were detected in 60 % (18) and G. duodenalis in 36% (11) of the samples examined. Few countries have laws that require regular monitoring of waterborne parasites in drinking water supplies and of their surveillance in wastewater treatment plants. Bivalvia are fundamental elements of the invertebrate biocoenosis in aquatic environments and are relatively site-faithful indicators. Owing to the filter-feeding habit of the bivalvia accumulation of parasite stages during filtration of hundreds litres of water is possible. Therefore, mussels could be perfect biomonitors for the detection of waterborne parasites.