Epidemiological Situation on Rickettsioses in the Russian Federation in 2013–2024 and Short-Term Incidence Forecast for 2025

The aim of the review was to conduct a comparative analysis of the epidemiological situation regarding rickettsioses in the constituent entities of the Russian Federation for the period of 2013–2024, and to provide a forecast of the incidence for 2025. In total, 1,380 rickettsiosis cases were registered in the Russian Federation in 2024, of which Siberian tick-borne typhus (STT) accounted for 938 cases, Astrakhan spotted fever (ASF) – 73 cases, rickettsiosis caused by Anaplasma phagocytophilum – 12 cases, rickettsiosis caused by Ehrlichia chaffeensis and Ehrlichia muris – 8 cases, Marseille fever – 6 cases. 57 (4.1 %) cases of rickettsiosis remained unidentified. In 2024, STT was recorded in 17 regions of the Russian Federation with an incidence rate of 0,64 0 / 0000 . The greatest contribution to STT morbidity came from the Siberian and Far Eastern Federal Districts. The calculated projected indicator for 2025 in Russia is expected to be 0.67 0 / 0000 . The ASF morbidity rate in Russia in 2024 was 0.05 0 /0000, while the calculated projected ASF morbidity rate for 2025 remains at 0.05 0 / 0000 . In 2024, it was possible to verify the causative agent of STT in autopsy material from three deceased individuals from Tyumen Region (n=1) and Novosibirsk Region (n=2). As a result of phylogenetic analysis, a new genovariant (genome isolate) of Rickettsia sibirica was identified in one sample.