Brucellosis: Trends in the Development of Situation in the World and Forecast for 2022 in the Russian Federation

Abstract

An analysis of trends in the development of situation on brucellosis in the world over past decade and the data on the main risk factors for the occurrence of epidemiological complications regarding this infection in various regions of the world are provided in the paper. An expert assessment of the current epizootiological and epidemiological situation on brucellosis, the coverage of population and animals with immunization in the Russian Federation is given. Over 9 months of 2021, 210 potentially hazardous as regards brucellosis in cattle areas and 24 sites – as regards brucellosis in small ruminants – were registered in Russia. Compared to the same period in 2020, there was a decrease in the number of newly identified hazardous sites for bovine brucellosis by 35.8 % (117 areas). However, long-term upward trend in epizootiological adversity for bovine brucellosis in Russia persists. The epidemiological situation on brucellosis in the country for the period of 2012–2021 is characterized as unfavorable. Decrease in the number of newly detected human brucellosis cases (by 25.1 % of long-term average values) is observed against the background of persistent unfavorable epizootic conditions for brucellosis among epidemiologically significant species of small ruminants and cattle in regions with developed animal husbandry. In 2021, clusters of human cases were registered in the Republic of Dagestan and Penza Region. In the Republic of Dagestan, against the background of aggravation of epizootiological and epidemiological situation on brucellosis, there was also an alarming trend towards prevalence of a relatively high incidence among minors. The proportion of cases of brucellosis among children under the age of 17 in the Republic amounted to 60.3 % of the total number of minors with newly diagnosed brucellosis in Russia over the past 10 years. Taking into account current epizootic, epidemic situations and the long-term dynamics of the development of situation on  brucellosis in the Russian Federation, the incidence of brucellosis among the population  is predicted to be 10–15 % lower than the average long-term values – 0.18–0.20 per 100000 of the population – in 2022. The number of human cases of brucellosis can range from 250 to 300.