Analysis of Brucellosis Incidence and Molecular-Genetic Characteristics of Brucella Population in the Territory of the Russian Federation

Abstract

An analysis of brucellosis incidence in Russia in 2013–2022 and the data on genetic diversity of Brucella melitensis and Brucella abortus populations isolated in Russia in 1939–2022 are provided in the review. Over the past decade, the epidemiological situation in Russia has been characterized as unstable against the background of persistent unfavorable conditions for brucellosis in cattle and small ruminants. During the period of 2013–2022 (9 months), 4298 epizootic foci as regards brucellosis in cattle (89164 sick animals) and 371 as regards brucellosis in small ruminants (13569) were registered. The largest number of epizootic brucellosis foci was recorded in the North-Caucasian and Southern Federal Districts. In 2013–2022, on average, 327 cases of brucellosis among people were registered annually, the incidence rate per 100 000 of the population was 0.24. Up to 70–90 % of brucellosis cases were detected in the south of the European part of the country. A trend towards deterioration of the situation on brucellosis in Volga (Penza and Samara Regions) and Central (Smolensk, Voronezh and Tula Regions) Federal Districts is observed. There is a connection between the intensity of epidemic manifestations of brucellosis and the level of anthropurgic enzooty of territories. In 2022, 467 cases of brucellosis were reported (0.32 per 100 000 of the population), which is 42.8 % higher than annual average values over 10 years. In 2023, a measure of stability of incidence rates, by 20–25 % above average long-term values, is to be expected. Incidence of brucellosis in humans will be within the range of 380–410 cases (0.26–0.28 per 100 000 of the population). The results of genotyping of B. melitensis strains point to an increase in the proportion of isolates with an MLVA-profile characteristic of strains from enzootic as regards brucellosis countries of Middle East and North Africa over past 20–25 years, which can indicate importation (introduction) of the infection from these territories to Russia through small ruminants and/or biomaterial from them.