Helminthiasis - diseases caused by parasitic worms - worms. Helminthic infections occur in people, animals and plants. Among the helminthiasis distinguish the trematodozov (see), cestodes (see), nematodes (see), acanthocephales (see). Geohelminthoses are called worms, larvae of pathogens which reach invasive stage in the external environment, bioeliminable - worms, larvae of pathogens which are developed in the body of man or animal.
Ways of infection by helminthes diverse and due to the biology of the parasite. Worms can get into the body with food (vegetables, fruits, undercooked meat and fish products), as well as through dirty hands, from the soil. Larvae of some of worms actively penetrate through the skin, larvae of other are transmitted by the bite of blood-sucking insects. The most widely helminth infections are common in children, because the infection of worms going through the soil and dirty hands (ascariasis, trichocephalosis, enterobiasis, gimenolepidoz). Geohelminths more common in areas with moderate and warm climate, mainly in people who are engaged in cultivation of agricultural crops. In cattle breeding areas are widespread Bioelements, larvae of pathogens which develop in the muscles of cattle (beef tapeworm infection) or pigs (tenis, trichinosis). People engaged in fishing, is more common difillobotrioz, and in some areas and opisthorchiasis. In the North is dominated by difillobotrioz, opisthorchiasis, liviococcia; in the middle lane, in the subtropics and tropics - ascariasis and trichocephalosis. The population of the countries with a hot climate is often affected by hookworm, the schistosomiasis and filaretai.
The clinical course of helminthiasis depends on the type of pathogen, the intensity of the invasion, the body condition of the patient and other factors. In the pathogenesis of helminthiasis play the role of sensitization of the body and the subsequent development of allergic reactions, toxic effects, mechanical damage of tissues, absorption of parasites in the blood and individual nutrients (vitamins, etc). When migrating worms are created conditions conducive to a secondary bacterial infection, for example in opisthorchiasis sometimes purulent cholangitis.
With repeated invasions develops or that the degree of immunity.
Diagnosis (table.) mainly based on the discovery in the faeces of eggs or larvae, parasitic worms various methods.
Currently, the following effective helminthological research methods faeces. Method Kato: 100 mg Cala put on a glass slide, cover with a strip of hydrophilic cellophane size 8 cm2 and press down with a rubber stopper. (Strips of hydrophilic cellophane pretreated by immersion into the solution of the following composition: 3% water solution malachite green to 6 ml, glycerin - 50 ml 6% solution of phenol - 500 ml. Strips in a liquid should not adjoin to each other. After 24 hours, they are suitable for use.) Microscopy is performed not later than one hour after preparation. During this time at room temperature smear several dries up and becomes more transparent, that facilitates detection of helminth eggs. In the hottest time of the year to avoid drying smear his research over 30-40 minutes Method Krasilnikova: in a bottle with capacity of 30ml pour 25-30 ml of 1% solution of detergent, washing powder "LOTOS". Powder pre-dried in the case at temperature of 100 degrees within 1-2 hours, making it 10 g and dissolve it in 1 litre of water. You can use other washing powders, but the concentration of the solutions will be different. Taken such maximum suspension powder which is dissolved in a given volume of water without any sediment. In the bottle with a solution of detergent put a piece of Cala the size of a large walnut. The bottle is covered with a plastic cap. Cal must be in solution of not less than one day. During this time at the bottom bottle is formed of two or three-layer sediment. In the middle layer concentrate eggs of helminths. Pasteur pipette with highly repulsed by the end close my finger and injected into the middle layer is not touching the bottom of the vial. Finger and push a solution with helminth eggs enters the eyedropper, then it is transferred onto a glass slide and examined under a microscope. In the solution of detergent helminth eggs are stored up to 6 months.
In recent years more and more important, especially in tissue helminths., acquires immunodiagnostics.
Cm. also Helminthological research methods.
Methods of treatment. In most cases, deworming (see) leads to faster recovery, however, some worms (echinococcosis, liviococcia) apply only surgical methods of treatment.
Prevention of helminthiasis includes a range of activities. Sanitation of settlements, the protection of soil and water from faecal pollution, disposal of sewage, intended for fertilizers and systematic fight against flies. Mass planned examination of the population with the purpose of revealing and treatment of infested with worms. Disposal by incineration or boiling invasive material, processing, boiling water or a solution of bleach stool and items used by the patient. Thorough washing of hands before eating, after visiting the toilet, ground contact. Thorough washing vegetables, fruits and berries; sufficient thermal processing of meat and fish products. Wide health promotion among the population.
In the diagnosis of parasitic infection, in addition to the major clinical signs, first of all use of survey data feces on eggs and larvae of worms (PSBs and eroscape). In some cases it is necessary to resort to the study of duodenal contents, sputum, blood, skin scrapings. Of great importance immunological research methods, in particular serological reactions and allergic diagnostic specimens with antigens of larvae or adults of worms. Allergic diagnostic specimens not indifferent for an organism of the person, as even a small amount of antigen when injected into the blood can sensitize the body and cause the development anaphylacticski phenomena until the shock. It's preferable to use of serological reactions. Considerable aid in the recognition of a number of worms have x-ray examination and application of radioactive isotopes (for example, a scan of the liver echinococcosis).
In the table (pdf, 127 KB) provides information on the duration of the so-called clinical and parasitological incubation periods. The first corresponds to the time interval from the moment of infection to the development of the first signs of the disease, the second defines the date of emergence (and hence the possibility of detection) in the secretions of eggs or larvae of worms.