Seroprevalence and associated risk factors of human brucellosis among occupational population in Binzhou, China: a cross-sectional study

Background Brucellosis remains a global public health challenge, particularly in regions with high levels of livestock farming like Binzhou. This study aims to investigate the seroprevalence and associated risk factors of brucellosis among occupational populations in Binzhou. Methods From January to December 2024, a cross-sectional study among occupational populations was conducted in Binzhou, China. A total of 1,312 participants were recruited through a multistage cluster sampling strategy. All participants underwent serological testing for brucellosis and completed a structured questionnaire. The Rose Bengal Plate Test (RBPT) was used as a screening test, followed by confirmatory Standard Tube Agglutination Test (SAT), with a titer ≥1:100 considered positive. Univariable and multivariable logistic regression were used to identify risk factors associated with seropositivity. Results The mean age of the 1,312 participants was 56.85 ± 12.78 years. The sample comprised 952 males and 360 females. The overall seroprevalence of brucellosis was 4.73% (62/1,312), Wudi County exhibited the highest seroprevalence at 11.39% (27/237), which was significantly higher than that of other regions ( χ 2 = 36.967, p 0.001). The seropositivity rate among males (5.5%) was also significantly higher than that among females (2.8%) ( χ 2 = 4.181, p = 0.041). Five Brucella strains were isolated and identified as B. melitensis , with an isolation rate of 8.06% (5/62). Having a history of contact with brucellosis patients (OR = 2.412, 95% CI: 1.181–4.924), having external injuries when in contact with livestock (OR = 2.298, 95% CI: 1.093–4.833), and sharing water sources (OR = 1.848, 95% CI: 1.002–3.410) were three independent risk factors associated with brucellosis infection within the occupational population. Conclusion The seroprevalence of brucellosis among the occupational population in Binzhou is high and is primarily driven by B.melitensis . The risk is strongly associated with work-related injuries, contact with infected individuals and sharing water sources. Targeted interventions, including occupational safety training, protective equipment, health education, and enhanced targeted surveillance in high-risk areas, are urgently needed.