Human brucellosis and associated risk factors in the Middle East region: A comprehensive systematic review, meta-analysis, and meta-regression

Introduction: Human brucellosis, caused by the bacteria Brucella, , is a significant infectious disease globally, also known as Mediterranean fever or Malta fever. Methods: This meta-analysis and systematic review focuses on the prevalence rate, risk factors, and diagnostic methods of human brucellosis in Middle Eastern countries, where the disease remains a significant public health issue. The analysis included 92 studies conducted between 1993 and 2024, following specified inclusion and exclusion criteria among symptomatic patients across these countries. The prevalence rate was calculated by dividing positive samples by total samples. The I2 index and Chi-squared test assessed study heterogeneity. Significant heterogeneity occurred when I2 exceeded 50 %. Results: The highest prevalence rate was observed in Oman, Lebanon, and Kuwait countries, emphasizing a notable burden of Brucella infection in these regions. Risk factors associated with human brucellosis were identified, with unpasteurized dairy consumption and close animal contact being predominant. Various professions such as farmers, dairy factory workers, and agriculture workers showed higher prevalence rate. Gender analysis indicated a prevalence rate of 18.02 % (95 % CI: 11.55-25.51 %) in males and 13.61 % (95 % CI: 10.8-16.68 %) in females, with no significant difference in hospitalization rates. The prevalence rate of Brucella spp. was varied across detection methods, with immunocapture agglutination assay (Brucellacapt) showing the highest estimated prevalence rate of (44.04 %, 95 % CI: 27.71-61.04), followed by PCR (39.84 %, 95 % CI: 20.14-61.39) and culture (29.22 %, 95 % CI: 17.89-42.03). Among Brucella species, Brucella melitensis (B. melitensis) and Brucella abortus (B. abortus) were the highest prevalence rate. Although statistically insignificant, the meta-analysis also revealed an upward trend in prevalence rate from 1993 to 2024, (P value = 0.277). Discussion: This comprehensive review emphasizes the need for tailored strategies to control brucellosis in the Middle East, highlighting the importance of timely diagnosis, public awareness, and effective treatment protocols. These findings provide valuable insights for policymakers and healthcare professionals working to mitigate the impact of this disease in the region.