Epidemiological and epizootological characteristics of ixodic tick — borne borreliosis in different natural zones of the Central Federal District of Russia

Based on the study of the materials of the state reports of the Federal Service and territorial departments of Rospotrebnadzor (the Russian consumers’ supervisor) of the Russian Federation «About the condition of sanitary and epidemiological welfare of the population» within the period of 2011–2020, the results of the analysis of incidence indicators and epizootological monitoring of ixode tick-borne borreliosis (ITB) in two clusters of natural zones of the Central Federal District (CFD) of Russia are presented — northern (zones of taiga, mixed and broad-leaved forests) and southern (zones of forest-steppes and steppes). Over the last ten — year period, the average incidence rates of ITB in the Russian Federation and in the Central Federal District are statistically indistinguishable — 4.78 and 4.79 per 100 thousand of population. The incidence of ITB in Russia has a moderate downward trend (average increase tendency-aver.incr.T = –4.0 %), in the Central Federal District it is characterized by stable dynamics (aver.incr.T = –0.3 %).The incidence of ITB in the Central Federal District is statistically significantly correlated with the proportion of people bitten by ticks (341.5 per 100 thousand people, Rh/y = 0.6). The incidence rate and the proportion of people bitten by ticks are characterized by higher values in the northern cluster of the Central Federal District (5.5 and 394.6 per 100 thousand people. respectively). In the southern cluster, they are 3.6 and 281.8 per 100 thousand people. respectively). There is a statistically significant correlation between these indicators in the northern cluster, as well as in the Central Federal District (Rh/y = 0.7). The tick infection rate in the Central Federal District has been 16.1 %, in the northern cluster — 14.4 %, in the southern — 17.8 %. There is no correlation between these indicators and the corresponding levels of incidence.