Spatial Distribution and Preventive Behaviours Towards Human Brucellosis in an Endemic Area: A <scp>PEN</scp> ‐3 Model‐Based Case‐Control Study

INTRODUCTION: Brucellosis is a bacterial zoonotic disease transmitted through contact with infected animals or unpasteurized products. Endemic in Iran, it causes fever, fatigue and muscle pain, posing significant public health and economic challenges. This study aims to investigate the factors influencing preventive behaviours against brucellosis in Hamadan Province, utilizing the PEN-3 model to explore cultural and social dynamics, alongside Geographic Information System (GIS) technology for spatial analysis of disease incidence. METHODS: This study was conducted in two sequential phases. In the first phase, with the aim of identifying geographical hotspots of human brucellosis, data on all confirmed cases reported in Hamadan Province between 2016 and 2023 were extracted from the national communicable disease surveillance system. Spatial analysis was carried out using ArcGIS version 10.8.2, and significant high-risk clusters were identified through the Getis-Ord Gi* statistical method. Based on the spatial clustering results, Kabudarahang County was selected as the study site for the second phase. In the second phase, a case-control study was conducted in 2024 in comprehensive health centers within Kabudarahang County. The study sample included 306 participants, comprising 102 cases (individuals with confirmed brucellosis) and 204 controls (healthy individuals). Brucellosis diagnosis was established according to the Iranian Ministry of Health's standard case definition, including positive serological tests such as Wright (≥ 1:80), 2ME (≥ 1:40), or Coombs-Wright. Data collection was performed using a researcher-developed questionnaire grounded in the PEN-3 cultural model, encompassing demographic characteristics, knowledge about brucellosis, perceptions, enabling factors, nurturing influences and preventive behaviours. The questionnaire's content validity was confirmed through expert panel evaluation using CVI and CVR indices, and internal consistency was assessed using Cronbach's alpha. Data were analyzed using Stata version 17. RESULTS: The study found that brucellosis was most prevalent in rural areas and among men, with an adjusted incidence risk of 8.95 per 10,000 people. Kabudarahang County was identified as the primary hotspot, with an incidence risk of 24.99 per 10,000 people. Protective factors included being female (OR = 0.44), higher education (OR = 0.41), better economic status (OR = 0.36) and higher preventive behaviour scores (OR = 0.92). Risk factors included working in livestock (OR = 5.40) or agriculture (OR = 2.14), consuming local dairy products (OR = 2.98), contact with livestock at home (OR = 6.56) and family history of brucellosis (OR = 11). Linear regression analysis indicated that knowledge, perceptions, enablers and nurturers explained 34% of preventive behaviours. CONCLUSION: This study emphasizes the importance of education and raising knowledge to reduce the prevalence of brucellosis. The findings suggest that effective prevention of this disease requires attention to the complex interaction of demographic, educational and behavioural factors. Using comprehensive models such as the PEN-3 model can help better understand the cultural and social determinants of health behaviours. Policymakers should develop and implement comprehensive educational and preventive programs that specifically address the needs and conditions of rural communities and individuals at risk.