[The structure of the nosogeographic range of opisthorchiasis in the Ob-Irtysh basin].

Results of our own investigations and available data in the literature concerning the epidemiology of opisthorchiasis in Ob-Irtysh river basin have been gathered, and geographic ranging have been established. The prevalence of infection, children's infection rate, the intensity of infection and clinical manifestation rate have been suggested as a criterion for division of territories into areas. 4 degrees of endemia was established: areas with sporadic incidence rate (prevalence is less than 1%); hyperendemic (prevalence 1-10%, intensity of infection 1-20 egg/gr., children's infection and clinical manifestation are absent), mesoendemic (prevalence 10-40%, children's infection rate 1-25%, intensity of infection about 300 egg/gr., clinical manifestation rate about 50%) and hyperendemic area (prevalence above 40%, children's infection rate 25-60%, intensity of infection above 300 egg/gr., clinical manifestation rate about 80%). Original map of pattern of opisthorchiasis distribution area is presented. The decreasing of transmission of O. felineus to periphery of basin is noted.