Immunological and epidemiological effectiveness of tularemia vaccination in the Donbass region

Objective: to evaluate the epidemiological and immunological efficacy of tularemia vaccination in the Donbass region from 1991 to the present.

Materials and methods: data on the incidence of tularemia, immunization coverage of the population, results of intradermal tests with tularin, agglutination reaction and indirect hemagglutination reaction with tularemia antigen were analyzed.

Results: since 2012, immunization against tularemia has not been carried out on the territory of the republic. Since 2015, this approach has resulted in the emergence of foci with multiple cases of human tularemia. Cases were registered on the territory of natural foci of Novoazovsky and Yasinovatsky districts. Since 2017, immunization of the population in enzootic territories has been resumed, planning and selection of contingents to be vaccinated was carried out in a differentiated manner. According to epidemic indications, 400 people were vaccinated from among those at risk of contracting tularemia. In 2020– 2022 vaccination was not carried out. In the five months of 2023, 520 people were vaccinated against tularemia, 80 people were revaccinated.

Conclusions: the use of tularemia vaccine in the Donetsk region for 70 years led to the containment of tularemia, demonstrating the epidemiological and immunological effectiveness of specific immunoprophylaxis. The armed conflict and the cessation of vaccination led to an increase in the activity of the epidemic process in natural foci among animals and a significant increase in the incidence of tularemia in humans.

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