INVASION OF FISH BY LARVAE OF THE FAMILY DIPHYLLOBOTHRIIDAE IN THE KHANTY-MANSI AUTONOMOUS OKRUG – YUGRA

Abstract

Two epidemiologically significant species of the tapeworm (D. latum и D. dendriticum) circulate in of the Ob-Irtysh basin within the Khanty-Mansi Autonomous Okrug. They have an unequal effect on the human body. The purpose of the science work is to determine the invasion of fish by larvae of tapeworms D.latum and D.dendriticum (Perch Perca fluviatilis, Ruff Gymnocephalus cernuus, Pike Esox lucius, Syrok Coregonus peled, Muksun Coregonus muksun, Nelma Stenodus leucichthys nelma) from waterbodies of the Ob River and its tributaries from 2013 to 2019 year. The study aim is to identify the main factors of transmission of the invasion (diphyllobothriasis) to population. The fish for parasitological research and species identification was caught in the Ob River and its tributary, the Vakh River, as well as Torm-Emtor Lake. The studies were carried out in the parasitological laboratory of the Center for Hygiene and Epidemiology in the Khanty-Mansi Autonomous Okrug – Yugra, Nizhnevartovsk, the Nizhnevartovsk District, in Megione and Raduzhny by the method of incomplete helminthological study of fish. The study results found in general a very high level of plerocercoid invasion of fish from the Ob and Vakh Rivers. It was noted that the pike had a significantly high percentage of infection with D. latum, 71.64%. The highest intensity of invasion and localization of larvae (the family Diphyllobothriidae) was on the abdominal wall of the fish, and then on walls and in the thickness of walls of esophagus and stomach, in eggs, and very few in muscle tissues.