HELMINTHESIS - diseases of humans, animals and plants caused by parasitic worms, or helminths. Among helminthiases, trematodoses, cestodoses, and nematodoses are distinguished. There are known cases of parasitization in humans of prickly-headed worms - scratches (see Acanthcephaliasis), as well as annelids. Depending on the development cycle of helminth pathogens, helminthiases are divided into geohelminthoses and biohelminthoses.
The ways and factors of helminth transmission are diverse and are due to the characteristics of the biology of the parasite. Eggs or larvae of pathogens of geohelminthiasis develop without the participation of an intermediate host. From the host's organism with feces, they enter the environment (for example, soil, iodine), they mature and become invasive, that is, capable of infecting a new host. A person is infected with geohelminthiasis more often through the mouth, where eggs or larvae get from contaminated hands, as well as vegetables, berries, fruits, with water and even dust, for example, with ascariasis, trichocephalosis. The larvae of the causative agents of hookworm infections, strongyloidosis actively penetrate the skin of a person in contact with contaminated soil (when walking barefoot, lying on the ground, etc.).
Pathogens of biohelminthiasis develop only with the participation of two or more hosts - the final (definitive), intermediate, and sometimes additional. A person becomes infected with biohelminthiases when eating insufficiently thermally processed beef with larvae of bovine tapeworm (teniarinhoz), pork with larvae of pork tapeworm (teniosis), freshwater fish with larvae of broad tapeworm (diphyllobothriasis), cat fluke (opisthorchiasis), clonorchis and ., crayfish and crabs with larvae of paragonimus (paragonimiasis); when drinking water, in which there are copepod cyclops, invaded by worm larvae (dracunculiasis); through hands contaminated with dog feces containing eggs or segments of echinococcus (echinococcosis). Infection with filariasis occurs during bloodsucking by arthropod carriers - mosquitoes, horsefly larvae, biting midges, in the body of which microfilariae develops.
In the pathogenesis of helminthiases, the sensitization of the body and the subsequent development of allergic reactions, the toxic effects of parasites, mechanical damage to tissues, the absorption of blood and nutrients (vitamins, etc.) by parasites play a role.
Distinguish between acute and chronic phase (stage) of helminthiases. In the acute stage, with a number of helminthiases, larvae migrate along the patient's tissues. In this case, conditions are created that facilitate the attachment of a secondary bacterial infection, for example, with opisthorchiasis, purulent cholangitis sometimes occurs.
The clinical course of helminthiasis depends on the type of pathogen, the intensity of the invasion, the condition of the patient’s body, and a number of other factors.
Diagnosis is mainly based on the detection of feces of eggs or larvae of parasitic worms using various methods.
Anthelmintic agents are used to treat helminthiasis. In most cases, deworming in combination with pathogenetic therapy (desensitizing agents, vitamins, etc.) contributes to a quick recovery, however, with some helminthiases (echinococcosis, alveococcosis), surgical methods of treatment are also used.
Prevention of helminthiasis includes a set of measures: sanitary improvement of populated areas, protection of soil and hearth from contamination with feces, neutralization of sewage intended for fertilizers, as well as systematic fight against flies; mass routine screening of the population in order to identify and treat persons infected with helminths; veterinary and sanitary supervision of meat in slaughterhouses, meat processing plants, markets, prohibition of the use of meat and meat products with viable helminth larvae; sufficient heat treatment of meat and fish products; washing hands before eating, after visiting the restroom, contact with the soil, caring for dogs; thorough washing of vegetables, berries and fruits; widespread health promotion among the population.