Results of Epizootiological Survey of the Territories of the Republic of Crimea and Sevastopol in 2015–2022

Introduction: Systematic studies of endemic zoonotic diseases on the Crimean Peninsula resumed in 2015 after a long break.

Objective: To specify boundaries and determine epizootiological activity of the natural foci of infectious diseases in the Crimea and to update the list of possible reservoir hosts and vectors based on the results of field studies conducted in 2015–2022.

Materials and methods: Counting and trapping of small mammals, ixodid ticks and mosquitoes, collecting of pellets of birds of prey, sampling of water and other zoological and entomological materials were carried out in the Crimea in the years 2015 to 2022.

Results and discussion: According to the results of epidemiological and epizootiological monitoring of the Crimean Peninsula, the samples tested positive for tularemia were collected on the territory of 14 administrative entities, leptospirosis – 21, hantaviruses – 12, tick-borne encephalitis – 2, Crimean-Congo hemorrhagic fever – 7, Lyme borreliosis – 21, West Nile fever – 3, Q fever – 2, Marseilles fever – 6, monocytic ehrlichiosis – 1, and granulocytic anaplasmosis – 8 entities. A new hantavirus was identified in the Leninsky district. Positive findings of markers of the Crimean-Congo hemorrhagic fever virus were registered not only in the main vector, but also in other species of ixodid ticks. True boundaries of the natural foci of Lyme borreliosis in the Crimea were much wider and ran through both forest and steppe zones. A stable reproducing population of epidemiologically significant Ae. albopictus mosquitoes was found on the southern coast of Crimea.

Conclusions: Based on the findings, we specified the boundaries and confirmed the activity of natural foci of infectious diseases during the study period, updated sources of infections, reservoir hosts and vectors, and compiled the List of enzootic (endemic) territories of the Crimea, on which circulation of infectious agents common to humans and animals was found based on the results of field material studies in 2015–2022, all facilitating managerial decisions on prevention of natural focal infections.

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