Ecological and epidemiological characteristics of tick-borne encephalitis and Lyme disease incidence according to the data of the Arkhangelsk region for 2012-2022

Abstract

Aims: retrospective ecological and epidemiologic analysis of the incidence of TBE and ITB in the Arkhangelsk region (AR) for 2012-2022 to assess the prediction of further prevalence of these diseases. Materials and methods: statistical data of the Unified Interdepartmental Information and Statistical System, as well as statistical annual forms of the Department of the Federal Service for Supervision of Consumer Rights Protection and Human Welfare in Russia and the Arkhangelsk region were used as the information base. The registered cases of TBE and ITB morbidity in the AR, as well as in Russia and the Northwestern Federal District as a whole for 2012-2022 were evaluated. Time series analysis was performed using Microsoft Excel 2019. The study also analyzes the dynamics of climatic factors in AO and its possible impact on the distribution and migration of ixodid ticks across the territory of the European North of Russia. Results: the number of tick bites in AR throughout the entire study period significantly exceeds the similar indicator (per 100 thousand population) in Russia. The incidence of TBE in AR significantly exceeds that in both RF and NWFD, and exceeded the all-Russian level by more than 3 times, although it had a faster rate of reduction (5.7% vs. 3.7% annually). The incidence of ITB has a paradoxical character due to the fact that throughout almost the whole period it is below the all-Russian level (3.19 per 100.000 population in AR against 4.41 in RF), while the incidence in NWFD is 1.3 times higher on average. Conclusion: the incidence of TBE in the territory of the Arkhangelsk region during the study period decreased, but was still far from the all-Russian level, the incidence of ITB had an average tendency to increase. The territory of AR is subject to the trend of increasing average annual temperatures, and anthropogenic interventions, in particular, abundant deforestation, lead to the destruction of established ecosystems and open new opportunities and territories for ticks, which in the future may negatively affect the established trends of morbidity. The analysis confirms the need to develop and adopt organizational measures aimed at the development of epidemiological and epizootological monitoring.