Public Health Risks and Intervention Strategies in Mass Religious Gatherings: A Systematic Review of Evidence from Arbaeen and Hajj (2000 - 2024)

Abstract

Context: Large-scale religious gatherings like Arbaeen pose significant public health risks due to extreme crowding, prolonged duration, and multinational attendance, which amplify infectious disease transmission, trauma, heat-related illnesses, and chronic disease exacerbations. Objectives: This systematic review synthesizes evidence (2000 - 2024) to evaluate health risks and interventions. Data Sources: Following preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, we searched six databases (PubMed, Web of Science, Scopus, Embase, ScienceDirect, Google Scholar) for English-language studies on Arbaeen, Hajj, and similar events. Study Selection: The studies were selected based on their relevance to the themes of infectious diseases, non-communicable diseases (NCDs), trauma, interventions, systemic challenges, and recommendations. Data Extraction: The data were thematically analyzed across the six domains mentioned above to synthesize evidence on health risks and interventions. Results: Among 8,644 records screened, 32 studies were included. Respiratory infections [COVID-19 (OR = 2.3, 95% CI: 1.8 - 2.9); MERS-CoV] and cholera (attack rate: 9.17%) predominated, driven by overcrowding (6 - 8 persons/m2) and poor sanitation. Antimicrobial resistance was significant (94.8% ciprofloxacin-resistant Neisseria meningitides). Hypertension (36.04%) and diabetes (14.78%) complications increased due to environmental stressors. Trauma (68.5% of cases) included fractures (28.1%) and blisters (20.9%). PCV-13 vaccination reduced Streptococcus pneumoniae carriage (OR = 0.15), while mobile health units improved care (β = -1.2, P = 0.03), though logistical gaps (e.g., 42% staff shortages) persisted. Fragmented governance (κ = 0.21) and surveillance limitations (sensitivity: Sixty-two percent) hindered responses. Conclusions: Integrated strategies addressing both infectious and non-communicable risks are critical. Prioritizing climate-resilient infrastructure, transnational collaboration, and innovative technologies (e.g., real-time surveillance) can enhance preparedness. These findings provide a blueprint for health security in mass gatherings (MGs) amid global mobility and climate challenges.