Soil as the source of infection

Being the dwelling place of pathogenic microorganisms, soil is another possible factor infections and diseases of human and animal parasitic protozoa; infection occurs through the ingestion of their dormant forms or cysts. A person infected cysts of Giardia (see Giardiasis) and other flagellate, dizenterina forming cysts (see Amebiasis), intestinal infusoria - balantidia (see Balantidia). A very significant role in soil factor in the contamination of humans, animals and plants, a large group of soil-transmitted helminths, including Ascaris (see Ascariasis), vlasoglavami (see Trichocephalosis).
Development of eggs of soil-transmitted helminths ends after separating them from the bowels of the owner, and the velocity of egg development is dependent on the availability of oxygen required humidity and temperature of the environment (in particular, the vertical temperature gradient), the degree of sun exposure, physical and chemical properties of soil. In unfavorable natural conditions egg development is slowed down or they perish. Invasive only eggs that contain Mature live larvae. Some of intestinal soil-transmitted helminths (Ancylostoma, some) larvae emerge from the Mature eggs in the soil and after additional development can penetrate the human skin. Through the skin becomes infected people intestinal pricey (Strongyloides stercoralis). Named helminths in the presence of sick people, and the absence or inadequacy of sanitary supervision can get spreading in deep mines. Larvae of Ancylostoma dogs and cats, extending from the soil to human skin and cause long not healing dermatitis. Human infection trichostrongylidae (Trichostrongylus colubriformis and others) occurs only in case of accidental ingestion their free larvae. Eggs of Bioelements (Cana), requiring an intermediate host, enter the soil is already in invasive condition. The main factors of distribution of protists and helminths - faecal contamination, especially when introduced in soil no untreated wastewater and sewage for growing vegetables, berries, as well as neglect of personal hygiene rules.
Recently, attention is paid to the relationship of the components of soil microflora (bacteria, predatory fungi, actinomycetes), protists between themselves and their influence on eggs and larvae of worms. Set the antagonistic action of soil amoeba (Amoeba albida) on mushroom pests of cotton. To control pathogenic soil nematodes man, animals and plants are being proposed in the soil the spores of predatory fungi hyphomycetes from the kind of Didymozoophaga. Admit the possibility of inhibitory action of actinomycetes and bacteria isolated from soil irrigated fields, the development of Ascaris eggs. Soil serves as a substrate for many ectoparasites, carriers of transmissible diseases (ticks, fleas, mosquitoes, flies, horse-flies). Some species of mites, beetles, flea larvae, ect., ants are intermediate hosts for worms. The soil is home to many insects - pests of agriculture and forestry, orchards and gardens.