[ASSESSMENT OF POTENTIAL RISK FOR CONTAMINATION OF SURFACE WATER RESERVOIRS BY PATHOGENS OF HUMAN PARASITIC DISEASES].

Sanitary and parasitological studies of the waste effluents and surface reservoir waters were conducted in the south of Russia. The efficiency of purification of waste effluents from the pathogens of parasitic diseases was investigated in the region's sewage-purification facilities. The water of the surface water reservoirs was found to contain helminthic eggs and larvae and intestinal protozoan cysts because of the poor purification and disinfection of service fecal sewage waters. The poor purification and disinvasion of waste effluents in the region determine the potential risk of contamination of the surface water reservoirs and infection of the population with the pathogens of human parasitic diseases.

[Results of parasitological passportization of sewage treatment works in the South Federal District].

Developed parasitological passports for sewage treatment works have been issued in the subjects of the Southern Federal District. Its some regions have areas inadequately covered by centralized water drainage. New waste treatment technologies and disinvasion agents have not been virtually introduced. No proper significance is attached to the parasitological studies of epidemiologically significant substrates, such as waste waters and their sludge. The positive results of dehelmintization and disinvasion are stated from the absence of helminth eggs rather than from the comparative results of sewer clearing from the invasion principle and their viability loss. Standard guides corresponding to the profile of objects are inadequately used in day-to-day work.

[The sanitary and parasitological characteristics of environmental objects in the south of Russia. Wastewaters and their precipitations].

The relative uniformity of helminthic eggs has been noted in the wastewaters of the Rostov Region, Krasnodar Territory, and the Republic ofAdygea. An ovogram is mainly presented by the eggs of Ascaris, Toxocaras, and whipworms. By taking into account incomplete dehelmintization during waste treatment, 5,000 to 1,080,000 helminth eggs may annually come into the water reservoirs where purified wastewaters are discharged, 33% remaining viable. Irrespective of the efficiency of dehelmintization, wastewaters and their precipitations continue to remain epidemiologically dangerous substrates and to create prerequisites for the spread of an invasive source in the environment, by risking the infection of the population with parasitic diseases.

[Impact of effect of natural disasters on the circulation of causative agents of parasitic diseases].

The southern region is marked by a high incidence of parasitic diseases and a significant contamination of environmental objects with the eggs and cysts of their pathogens. Background examinations revealed the greatest soil contamination with helminthic eggs in the Temryuksky District of the Krasnodar Territory and in the towns of Vladikavkaz and Digora of the Republic of North Ossetia (Alania). The least contamination was found in Rostov-on-Don and the towns of the south-western area of the Krasnodar Territory. The eggs of Toxocara and astamination. There is an increase in the proportion of soil positive tests from 26.6 to 50.0, with the high (up to 82.0-100.0%) viability of eggs and a rise in the intensive index of their content per kg of soil (from 2.7 to 4.7-11.0). Toxocara eggs were mainly detected. The established high proportion of seropositive persons (10.7-18.0%) among the local population is an additional verification of the wide circulation of Toxocara eggs in nature. By the helminthic egg contamination index, the soils of localities of the south of Russia are qualified as those of moderate epidemic hazard. The floods accompanied by the increased helminthological contamination of the upper soil layer may lead to a higher human risk for contamination with helminthic diseases.