Risk Factors of Human Brucellosis in the Northeast of Iran

Introduction: Brucellosis is a major health problem in northeast of Iran. There is not much data on the association of nutrition and lifestyle factors with the risk of brucellosis in this area. We conducted the present study to determine the risk factors of brucellosis in Khorasan-e Razavi Province, northeastern Iran. Methods: we conducted a case-control study from July 2015 to March 2016 in three cities of Khorasan-e Razavi Province. Cases and controls were recruited from individuals attending primary care and were matched together based on their age (± 2 years) and gender. Clinical and epidemiological data were collected with a valid questionnaire. Conditional logistic regression was used in Stata software V13. Results: We recruited 180 incident cases and 360 controls, of which 53.9% were male, and 90.0% were living in rural areas. Consumption of unpasteurized yogurt (OR): 5.4; 95% CI: 2.5-11.5), milk (OR: 6.0; 95% CI: 3.0-11.9), and cheese (OR = 3.7; 95% CI: 1.7-8.1), as well as engagement in livestock-related occupations (OR: 2.6; 95% CI: 1.2-5.2) significantly increased the adjusted risk of brucellosis. Conversely, having academic education (OR: 0.1; 95% CI: 0.01-0.5), consuming unpasteurized butter (OR: 0.4; 95% CI: 0.2-0.8), and timely animal vaccination (OR: 0.3; 95% CI: 0.1-0.5) had a protective effect on brucellosis. Conclusion: The risk factors identified in this study are lifestyle- and occupation- related modifiable factors. So, the disease incidence is expected to decrease in this region with modification of these risk factors, such as animal vaccination, personal protection at work, and public health education.