Analysis of the Global Plague Epidemiological Situation in 2025 and a Forecast of the Epizootic Activity of Its Natural Foci in the Russian Federation for 2026

The aim of this study was to analyze the global plague epidemiological situation in 2025 and forecast the epizootic activity of natural foci of this particularly dangerous infection in the Russian Federation for 2026. Between 2016 and 2025, a continuing downward trend in the epidemic activity of natural plague foci was noted in many regions of the world. The total number of cases was 5,626, of which 516 were lethal (lethality rate – 9.2%). In 2025, cases of plague were registered in four countries: the Democratic Republic of the Congo (41 cases, 2 fatal), the Republic of Madagascar (18 cases, 7 fatal), the United States (5 cases, 1 fatal), and Mongolia (3 cases, 1 fatal). All in all, 67 cases of plague were reported, of which 11 (16.4%) were fatal. In the Russian Federation, despite the presence of epizootically active natural foci, epidemiological stability in terms of plague was ensured in 2017-2025. During the analyzed period, animals infected with plague were detected in three natural foci: the Central Caucasian high-mountain, Gorno-Altai high-mountain, and Tuva mountain ones. Over the past decade, a total of 337 strains of the plague pathogen have been isolated in the plagueendemic territory of the Russian Federation. The total area of identified plague epizootics was 14,570 km² (6.5% of the total foci area). In 2025, localized plague epizootics were registered in the Karachaevsky district of the Karachay-Cherkess Republic and the Elbrus district of the Kabardino-Balkarian Republic, the Kosh-Agach district of the Altai Republic, and the Mongun-Taiga Kozhuun of the Tuva Republic. Plague-infected animals were detected in three (the Central Caucasus Highland, Gorno-Altai Highland, and Tuva Mountain) of the 11 natural plague foci in the Russian Federation. The total epizootic area was 523,01 km². A total of 13 plague pathogen cultures were isolated in 2025, including 12 isolates of the 4.ANT phylogenetic branch of the ancient biovar and one isolate of the 2MED0 phylogenetic branch of the medieval biovar of the main subspecies – Yersinia pestis pestis. It is noted that from 2017 to 2025, annual preventive (anti-epidemic) measures in epizootically active natural plague foci had a consistent significant salutary effect in enzootic territories. In 2026, the low epizootic potential of lowland natural plague foci in the Caspian and Transbaikal regions will be retained. A forecast for the development of local plague epizootics in the Karachay-Cherkessia, Kabardino-Balkarian, Altai, and Tuva republics in 2026 has been developed.

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