Hard ticks (Ixodidae, Acarina) are long known as vectors of various diseases of man, as well as of domestic and wild animals. Widespread in almost all of the climatic zones, except circumpolar ones, ixodids as blood-suckers can transmit a vast range of pathogenic microorganisms. It is therefore hardly surprising that these ticks, in particular those representing the genus Ixodes, have been extensively studied. To give just a few examples, the occurrence dynamics of ticks and tick-borne pathogens has been investigated in various geographical regions differing in climate, altitude and dominating vegetation communities. Tick distribution areas have been described, and their changes under the conditions of global climate warming have been forecasted. Alterations of genetic and biochemical features of infected ticks under the influence of pathogens have been analyzed, and the role of migratory birds in the transfer of ticks and their pathogens has been revealed.
The present monograph aims at somewhat filling in this gap. It summarizes the results of long-term studies on the parasitic system "ixodid ticks-tick-borne pathogens". Changes in the functioning of this system under the influence of growing anthropogenic pressure were revealed, and an increased epidemiological hazard of the system with altered properties was demonstrated.