Mass Gatherings Health Management in Arbaeen-Iran: A Successful Model for Infectious Disease Control in Global Mass Gatherings

Introduction: Religious mass gatherings, particularly the Arbaeen pilgrimage, pose substantial risks for the spread of infectious diseases due to their high crowd density and extensive international movement of pilgrims. Due to this unique circumstance, building and executing a robust health surveillance system is not only advantageous but also necessary for mitigating epidemic risks. The research study aimed to analyze the operational performance of the Mehran border crossing's health surveillance system as well as the impact of public health interventions between 2022 and 2024. Methods: This descriptive-analytical study utilized secondary data collected from healthcare monitoring systems, operational reports, and official statistics provided by the Islamic Republic of Iran's Ministry of Health, specifically at the Mehran border crossing. Key variables, including the number of health services delivered, syndromic screening indicators, the effectiveness of environmental interventions, health education outreach, and population coverage, were thoroughly evaluated and analyzed. Results: Over the course of three years, 9 million pilgrims received healthcare services, with 39000 cases identified and 32000 samples collected. The COVID-19 positivity rate (12%) and the El Tor test (cholera) (4.65%) showed good diagnostic accuracy at the point of service. Furthermore, a 72% increase in human resources by 2023 resulted in a 54% increase in case detection. Environmental activities, including health education, hygiene kit distribution, restroom cleaning, and monitoring of water/food safety, resulted in a 30% reduction in unnecessary hospital visits. The time pattern of visits revealed that 85 percent of services were concentrated in the seven days surrounding Arbaeen. Notably, the incidence of El Tor fell by 82% in 2023 and 91% in 2024, respectively. In contrast, respiratory infections surged in 2023 but decreased by 60% in 2024 as a result of targeted efforts. Conclusion: The strategic combination of active surveillance, health education, environmental interventions, and human resource management is crucial in mitigating the burden of communicable diseases in large populations. This comprehensive strategy has the potential to be a successful model for other religious and national celebrations around the world.