The Impact of Climate Change on Natural Foci of Plague and Tularemia in Armenia

The aim of the work was to use climate forecasts, including those from the Intergovernmental Panel on Climate Change (IPCC), in relation to Armenia to assess how climate changes could affect the habitat and populations of main reservoirs of plague and tularemia, as well as the epizootic potential of the territories; to develop ecological niche model of a natural-focal infectious disease by the example of tularemia focus in the southeastern region of Armenia under modern conditions and a forecast of the situation for 2040–2050.

Materials and methods. The work used forecast scenarios of changes in average annual temperatures and precipitation, literature data on the impact of climate change on the foci of particularly dangerous infections, and data from epizootiological survey. The model of the ecological niche of the tularemia focus in the southeastern region of Armenia was developed applying artificial intelligence.

Results and discussion. The currently registered and projected climate changes in Armenia, characterized by an increase in average annual temperatures and a decrease in average annual precipitation, will lead to an enlargement of arid areas in the republic. In this regard, the observed expansion of the little gerbil range to the north suggests the risks of epizootic manifestations of plague caused by the circulation of strains belonging to the main subspecies of Yersinia pestis ssp. pestis, in the border areas of the Transcaucasian high-mountain and the Pre-Araks low-mountain natural plague foci. Changing conditions affect the dynamics of the range of the common vole, contributing to the movement of its populations to optimal habitats located at altitudes higher than 2000 m above sea level, within which epizootic and epidemic risks for plague and tularemia are likely to increase. The predictive model of the ecological niche of the tularemia focus, developed for the southeastern region of Armenia, showed a reduction in the number of abiotic factors suitable for the circulation of the tularemia pathogen, which will lead to a 3–4-fold decrease in the intensity of epizootic manifestations of tularemia by 2040–2050.

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