Epidemiological Situation on Tick-Borne Spotted Fever Group Rickettsioses in the Russian Federation in 2012–2021, Prognosis for 2022–2026

Abstract

The aim of the review was to characterize the epidemiological situation on rickettsiosis of the tick-borne spotted fever (TSF) group in the constituent entities of the Russian Federation in 2012–2021 and provide a long-term forecast for 2022–2026. In 2020–2021, indicators of registered incidence of tick-borne rickettsiosis in Russia on the whole decreased relative to the average long-term pre-pandemic level in 2012–2019 by 2 fold for all forms of the TSF group on average (Siberian tick-borne typhus – STT, Astrakhan spotted fever and Mediterranean fever). A comparative analysis of the territories revealed a correlation between the incidence of STT and the number of medical facility visits due to “tick bites” (r=0.67, p=0.015), which, against the background of an increase in the frequency of contacts of the population with vectors in 2020–2021 in most regions and a decrease in the incidence in the same regions indicates the credible nature of the changes. The ranking of territories according to average long-term incidence rates made it possible to classify the Republic of Altai and the Altai Territory as regions of extremely high epidemic hazard as regards STT; high hazard – the Republic of Tuva; above average – the Republic of Khakassia, Khabarovsk Territory and the Jewish Autonomous Region. The established downward trend in the incidence of tick-borne rickettsiosis among the population will be sustained in most entities of the Russian Federation within the next 5 years, excluding the Republic of Altai, the Altai Territory, the Republic of Crimea and the city of Sevastopol, where current incidence or an increase should be expected. The results of the analysis indicate the need to put more emphasis on natural-focal infections at the time of COVID-19 pandemic.