Group case of brucellosis in livestock workers: clinical and epidemiological aspects

Brucellosis is a classic zoonotic, particularly dangerous and socially significant infection that remains a serious medical and social problem in many countries, including the Russian Federation.

In 2023, after more than a decade of prosperity in the Republic of Tatarstan, specialists registered an outbreak of bovine brucellosis with human infection. The main causative agent was Brucella abortus.

The study aims to perform a clinical and epidemiological analysis of the outbreak of occupational brucellosis in livestock workers.

The authors analyzed 11 cases of acute brucellosis (clinical examination, laboratory and serological methods, dynamic observation) and used parametric and nonparametric statistical methods.

During the outbreak of bovine brucellosis, out of 111 contacts, the diagnosis was confirmed in 20 (18.1%), of which 11 were under observation at the occupational pathology center. The disease was moderate in severity with common symptoms (weakness, subfebrile fever, arthralgia in the knee (63.6%) and shoulder (54.5%) joints). Laboratory examination revealed no significant deviations in the overall clinical parameters. The most informative serological method at the onset of the disease was Huddlestone's agglutination reaction (81.8% of positive results). None of the methods demonstrated absolute (100%) sensitivity. The transition from acute to chronic was observed in 91% of patients (the average chronization period was 224 days).

An important condition for the prevention of the disease should be strict compliance with the regulations for mandatory preliminary and periodic medical examinations of persons engaged in animal husbandry, as well as timely preventive, diagnostic, restrictive and other measures aimed at preventing the spread and elimination of foci of brucellosis.

Limitations. The limitations of the study are the small sample (n=11), the retrospective nature of the collection of part of the epidemiological data, as well as the analysis of only one outbreak in one region, which limits the possibility of generalizing the results.

Ethics. The research conducted did not require the conclusion of the ethics committee.

Contributions:
Arkhipov E.V. — research concept and design, text writing, editing;
Garipova R.V. — research concept and design, text writing, editing;
Safina K.R. — working with primary material, writing text;
Gorblyansky Yu.Yu. — research design, editing;
Abramova R.I. — working with primary material, writing text;
Safuanova L.I. — working with primary material, writing text.

Funding. The study had no funding.

Conflict of interest. The authors declare no conflict of interest.

Received: 28.05.2026 / Accepted: 17.06.2026 / Published: 27.07.2026

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