Trematodoses are helminthiases of humans and animals, caused by flat parasitic worms belonging to the class of trematodes (flukes).
Trematodes have organs of fixation - muscle suckers (oral and abdominal). A double layer of musculature is located under the covering tissues of the trematodes; there are nervous, excretory, sexual and digestive systems. Almost all trematodes are hermaphrodites, only schistosomes are dioecious. The sizes of various species of trematodes vary from a few millimeters to 2-7 cm. Eggs of some species of trematodes swallow mollusks when they enter the water, and the larvae of others that have hatched from eggs actively penetrate into the mollusks - intermediate hosts. The development and reproduction of trematode larvae occurs in mollusks. Some species of trematodes, in addition to intermediate ones, also have additional hosts - fish, crabs, and crayfish.
Many trematodoses are found in humans, domestic and wild animals. Some trematodoses (opisthorchiasis, clonorchosis, metagonymoz, etc.) become infected by eating raw or freshly salted fish , others by drinking water from stagnant water bodies and eating wild water plants ( fascioliasis ). Schistosome larvae float in water and actively enter the bloodstream through the skin. The spread of trematodoses contributes to the pollution of water bodies with the feces of patients containing larvae.Go
In the pathogenesis of trematodosis, sensitization of the patient's body by metabolic products and the disintegration of trematodes with the subsequent development of allergy, the manifestations of which are especially pronounced in the early phase of trematodosis, are of great importance. It should also take into account the mechanical effect of worms on the fabric.
After 2-4 weeks after infection, fever, pain in muscles and joints, puffiness of the face, gastrointestinal disorders, often a cough; increase in a liver, sometimes spleen is noted. In the blood - an increase in the number of leukocytes and eosinophilia . In the late phase, the clinical manifestations are largely associated with the localization of trematodes — opistorhis, clonorchis, fasciol in the liver, paragonimus in the lungs, metaponyms in the intestine, etc.
Trematodoses are diagnosed with the detection of helminth eggs in feces and duodenal juice, and with urinary schistosomiasis - in the urine.
In the prevention of trematodozov sanitary and educational work and treatment of patients are of great importance; it is necessary to clarify the danger of eating raw and lightly salted fish.
In some cases, there is a struggle with the intermediate hosts of trematodes, mollusks. Some types of trematodoses are almost ubiquitous (fascioliasis), others are limited to certain areas; Thus, opisthorchiasis predominates in Western Siberia, clonorchosis in the Far East, schistosomiasis is confined to tropical and subtropical regions. Based on the availability of certain trematodoses, specific measures are planned to combat them.