| Typically, between 2 to 3 million Muslims from over 183 countries participate in Hajj each year, and the Kingdom aims to increase this number. As for Umrah, around 25 million Muslims performed it in 2022, including 8 million from outside the Kingdom. These large gatherings of travelers present an opportunity for diseases to be transmitted within the crowd or to local communities, and they may also export diseases upon returning to their home countries. ----------- What is a mass gathering? A mass gathering is typically defined as a large number of people assembled in a specific location for a defined purpose—such as religious seasons like Hajj—where the size of the gathering is sufficient to strain local resources. Travelers to these gatherings face unique risks, as such events are associated with the transmission of infectious diseases due to crowding and poor hygiene practices. Additionally, crowds are exposed to non-communicable risks such as heatstroke and environmental hazards. ------------ What is Mass Gathering Medicine? Mass Gathering Medicine is a healthcare specialty focused on the planning, coordination, and delivery of medical services during events that attract large numbers of people—enough to place significant strain on local health and security systems. This specialty addresses a wide range of challenges, including communicable and non-communicable diseases, environmental hazards, potential disasters, and participant safety. ------------ What are the health challenges associated with mass gatherings during Hajj? The Hajj season presents a complex public health challenge, particularly as 37% of pilgrims are over the age of 60 and many suffer from chronic illnesses. Pilgrims are also exposed to unique conditions, such as walking over 50 kilometers across five days. Major health challenges during Hajj include managing infectious diseases—especially respiratory illnesses—health issues related to heat stress, and concerns about the provision and accessibility of medical services. ------------ What is the appropriate ratio of healthcare workers for managing crowds? Saudi Arabia provides medical care for pilgrims, with approximately 30,000 healthcare professionals participating in their service. According to the World Health Organization, there is no universal ratio of healthcare workers suitable for all mass gathering events, as requirements vary based on the type, duration, audience characteristics, and environmental risks of the event. However, evidence suggests that low-risk events may require one healthcare worker for every 1,000 to 2,000 participants, while high-risk events—such as Hajj—may require higher staffing levels, such as one healthcare worker per 500 participants or fewer, depending on risk assessment. In the case of Hajj, the Kingdom maintains a ratio of roughly one healthcare worker per 200 pilgrims, deployed across various zones through field hospitals, mobile clinics, and rapid response teams. ------------ Catastrophic Incidents in Mass Gathering Medicine Catastrophic incidents are a particular concern during mass gatherings, especially in extremely dense crowds. Many such events have occurred due to poor crowd management, structural collapses, fires, or acts of violence. Common causes of death include stampedes resulting from overcrowding, disorganization, and the lack of safe exits. In such cases, mass gathering medicine intersects with disaster medicine, shifting the focus from prevention to immediate intervention aimed at minimizing casualties. ------------ Saudi Arabia and Mass Gathering Medicine: Global Leadership Rooted in Hajj Hajj is one of the largest recurring human gatherings on Earth, bringing with it unique public health challenges that require a specialized approach to crowd management and medical care during large-scale events. In this context, Saudi Arabia has played a pioneering role in developing what is now known as Mass Gathering Medicine—a modern medical specialty focused on health preparedness and response during major gatherings. Over decades of organizing Hajj and Umrah seasons, the Kingdom has accumulated advanced operational and technical expertise, making it a global reference in areas such as health readiness, epidemic control, free healthcare provision, medical technology integration, and rapid emergency response. Building on this distinctive experience, the Saudi Ministry of Health, in collaboration with The Lancet Infectious Diseases, organized the first International Conference on Mass Gatherings Medicine in Jeddah in 2010. The conference concluded with the Jeddah Declaration, which laid out a global roadmap for formalizing this emerging discipline and called for the establishment of an international authority on mass gathering health, to be headquartered in Saudi Arabia. In response, the Global Center for Mass Gathering Medicine was established in Riyadh in 2012 through a strategic partnership between the Saudi Ministry of Health and the World Health Organization. Since that inaugural event, the Kingdom has hosted two more international conferences in 2013 and 2017, and reaffirmed its commitment to this field during the fourth international conference held in Jeddah in 2019 and in 2023—solidifying Saudi Arabia’s ongoing leadership in advancing health security for mass gatherings worldwide. ------------ The Saudi Commission for Health Specialties: Structuring Competencies and Building Capacity The Jeddah Declaration explicitly designated the Saudi Commission for Health Specialties (SCFHS) as a key entity in developing comprehensive training programs for Mass Gathering Medicine. In alignment with this mandate, the Commission is currently working—alongside the Global Center for Mass Gathering Medicine in Riyadh—on developing a competency framework and specialized training courses. This framework aims to define the essential knowledge, skills, and behaviors required from healthcare professionals at all levels, enabling them to effectively manage complex scenarios, including epidemics, heat-related illnesses, and disaster medical response. In addition, the SCFHS oversees the Disaster Medicine Fellowship Program—an advanced training pathway designed to equip physicians with expertise in emergency health response, disaster preparedness, and epidemic control. This program is closely linked to Mass Gathering Medicine, providing it with highly trained professionals capable of operating in high-pressure, complex environments such as Hajj, Umrah, and other major public events. | 
