[Role of endoparasites of fleas of wild rodents in plague enzootia].

Laboratory studies of fleas for gregarines have established that it is the latter inhabiting the intestine and stomach of the fleas of wild rodents which are of much interest as protozoa, in whose organism, parasitic species of bacteria can survive. Penetration of plague bacteria into the endoplasm ofgregarines and their possible survival in the cysts may create an additional component in the chain of an epizootic process, which ensures its function, without involving the rodents at the nesting biocenotic level following the pattern: flea imagoes - nesting litter infected with gregarine spores, cysts - flea larvae - flea imagoes infected with cysts, with the plague pathogen emerging into a rodent population through the imago of blocked fleas.

[Epidemiological situation on tularemia in the regions of Stavropol Territory affected by flood].

The data obtained in the analysis of the epidemiological situation in tularemia in the zone of inundation in the Stavropol Territory in 2002 are presented. The current systematic epidemiological surveillance, as well as the data of urgent epizootological and epidemiological survey in the zone of inundation permitted the objective prognostication of the situation in tularemia and formed the basis for the rational planning and realization of prophylactic measures.

[Hyalomma marginatum Koch in Stavropol' region].

Ixodes ticks of the species Hyalomma marginatum are widely spread in the semidesert and steppe landscape zones of the Stavropol Territory. The circle of the main hosts for the larvae and nymphs of these ticks includes many species of wild and domestic birds, European brown hare, four-toed and eared hedgehogs. Rodents are of no great importance for ticks as a feeding source.

[Study of the natural sensitivity of Ixodes to insecticides].

The article deals with the results obtained in the study of the natural sensitivity of the nature populations of Ixodes ticks to 4 insecticides. As revealed in this study, the ticks are highly sensitive to commercial preparations in different phases of their development. The selective sensitivity of different species of ticks to these preparations is noted.

[Specific features of the parasitic system of Crimean haemorrhagic fever in Stavropol' region during epidemic season of 2000].

Information on Crimean haemorrhagic fever (CHF) in different climatic zones of the Krasnodar territory is presented. The epidemiological importance of some species of Ixodes ticks as vectors of the causative agent of CHF was shown. Ticks Hyalomma marginatum proved to be the main vector species: they constituted 75-100% of all ticks collected from cattle, reaching the peak of their abundance in May.