[The clinico-epidemiological characteristics of opisthorchiasis foci in the Yamalo-Nenets Autonomous Okrug and the treatment results with praziquantel].

A clinical and epidemiological study of opisthorchiasis foci in the Yamalo-Nenets Autonomous Okrug was carried out. 764 people were surveyed, including 473 aborigines of the north, 207 denizens, and 84 migrants. Opisthorchiasis infection rate in villages was 40.5-45.7%. The intensity of infection was lower than 200 eggs per g faeces. The modelling of opisthorchiasis prevalence performed after Muench showed the highest correlation with the "simple" and "reversible" models. Factors determining the infection spread and limiting its intensity and those influencing the effect of chemotherapy were defined. Theoretically determined radical suppressive low-dose praziquantel chemotherapy was carried out. The efficacy of the drug, 25, 30, 40 and 50 mg/kg, varied from 76.5 to 92.0% (mean 88.1%), and the decrease of the egg density was more than 60%. The incidence of side effects of the therapy averaged 45.3%.