Issues of the presence of parasitic protozoa in surface waters

Abstract

Abstract. Parasitic protozoa are very numerous organisms in the environment that play an important role in the spread of water-borne diseases. Water-borne epidemics caused by parasitic protozoa are noted throughout the world. Within these organisms, intestinal protozoa of the genera Cryptosporidium and Giardia are ones of the most serious health hazards for humans. This paper focuses on the problem of the presence of parasitic protozoa in surface waters. Characteristics of the most frequently recognized pathogens responsible for water-borne outbreaks were described, as well as sources of contamination and surface waters contamination due to protozoa of the genus Cryptosporidium and Giardia were presented. The methods of destroying the cysts and oocysts of parasitic protozoa used nowadays in the world were also presented in a review.

Methods Used in Disinfections of Wastewater and Sewage Sludge – Short Review

“…Generally, in biological wastewater treatment processes, the efficiency of removing the microorganisms is higher than at the mechanical stage, ranging from 90 to 98%. At the same time, it should be remembered that traditional methods of wastewater treatment do not significantly reduce the number and viability of protozoan cysts and oocysts [25,26]. Currently, in water and rather wastewater technolo-gy, disinfection is one of the basic barriers preventing and limiting the spread of microorganisms causing diseases of aquatic origin, which aims at protecting a public health and reduce the risk of illness among people.…”