The Influence of Climatogeographic Conditions on the Expansion of the Range of Ixodes Ticks

Abstract

Global warming contributes to the widespread spread of some of the main vectors of natural-focal infections. Ixodid ticks can inhabit large numbers both in woodlands and in meadow and pasture areas. Recent decades have seen a shift in the habitats of many parasites to the northern regions, which contributes to the survival and reproduction of not only the vectors themselves but also to the completion of the development cycle of ticks. The growth of the population size and duration of the spring-autumn period of tick activity increases the period of the epidemic season. The epidemiological situation is complicated by the persistence and almost constant activity of natural foci of arthropod-borne infections. Weather conditions, precipitation, humidity (relative humidity of at least 85%), and air temperature affect the life cycle and range of ixodid ticks. These factors make a certain contribution to geographical expansion due to changes in the habitats of vegetation and carriers in the wild (animals, birds, and rodents), which carry ticks to new territories. The northern border of the area of ixodid infections – viral tick-borne encephalitis and ixodid borreliosis - lies now beyond the borders of the Arctic. However, there is evidence of a possible movement of these boundaries to the north, so the southern part of the Arctic region may fall into the zone of potential risk of transmission of these infections.