SUMMARY
The aims of this study are the enumeration of fecal contamination indicators, parasites and microfauna isolated throughout the wastewater treatment by the activated sludge process in a wastewater treatment plant located in Médéa (North West of Algeria). The results revealed no pathogens germs and removal efficiencies exceeding 90% for total coliforms, faecal coliforms, streptococci, ASR and parasites.However, the results showed richness in fecal contamination germs and helminth parasites with values that exceed OMS standards for discharge into the receiving environment.During the study, were observed groups of testate amoebae, nematodes, attached ciliates and ciliates free natantes characterizing the process with good purification and as the structure of the flocs between ideal and filamentous bulking. The results were rather satisfactory in terms of protozoa recognition.There is therefore need for additional microbial pathogen monitoring in the WWTP to minimize public health risk.