Travel to Mass Gatherings


Mass gatherings are typically defined as large numbers of people (1,000 to >25,000) at a specific location, for a specific purpose. More practically speaking, a mass gathering can be thought of as any assembly of people large enough to strain local resources. Travelers to mass gatherings face unique risks because these events are associated with environmental hazards, increased infectious disease transmission due to the influx of attendees, crowding, poor hygiene from temporary food and sanitation facilities, and challenging security situations.

Characteristics of Mass Gatherings

Medical providers preparing travelers for international travel and travelers themselves should understand the characteristics of mass gatherings. Some can be spontaneous, such as political protests; others are planned events. Some mass gatherings regularly occur at different locations, (the Olympic Games or the FIFA World Cup, for example) while others recur in the same location, such as the Hajj or Wimbledon. Table 9-4 provides a representative (albeit not comprehensive) list of scheduled, upcoming mass gatherings, including type (religious observance, sporting event, art and music festival), location, dates, and anticipated numbers of attendees.

Mass gatherings can be described effectively in terms of their location, venue, purpose, size, participants, duration, timing, activities, and capacity.

  • Location: Factors to consider include the host country, available infrastructure, the local environment, and the adequacy of security arrangements.
  • Venue: Facilities vary widely, and events may be held indoors or outdoors. Food, water, and sanitation, may be of varying quality.
  • Purpose: Mass gatherings can be political, religious, social, or athletic; the purpose of an event can affect the activities and mood of participants.
  • Size: The density of crowds at a mass gathering, rather than just the specific number of attendees, can further increase health risks. More densely packed crowds can facilitate disease spread or induce riots or crowd crush disasters.
  • Participants: Attendees may represent a unique demographic, such as a religious or political group, or may vary by features such as sex or age (for example, older adults attempting to complete a religious pilgrimage toward the end of their life).
  • Duration: The longer an event lasts, the more likely it is that local resources will be depleted and become strained.
  • Timing: Mass gatherings and local capacity are affected by the timing of an event. Weather, heavy tourism, and other factors can affect the ability of a host to organize a safe mass gathering.
  • Activities: Understand the activities involved at the mass gathering. Some may be risky or strenuous (e.g., walking a long way in extreme temperatures) or may involve alcohol or drug use.
  • Capacity: Hosts differ in terms of their ability to detect, respond to, and prevent public health emergencies. Understanding what health outcomes have been previously associated with recurring mass gatherings can help travelers prepare for future events.

Table 9-4. International mass gathering events, 2019–2022

Event type

Event name


Upcoming Dates

Projected Attendance

Religious events

Kumbh Mela

Multiple locations in India: Allahbad, Haridwar, Madhya Pradesh, Maharashtra

2019 in Allahbad

2022 in Haridwar

40 million

Arba’een Pilgrimage

Karbala, Iraq

October 2019

22 million

Grand Magal of Touba

Touba, Senegal

October 2019

3 million


Mecca, Saudi Arabia

August 10, 2019

July 30, 2020

2.5 million

Iztapalapa Passion Play

Mexico City, Mexico

Good Friday (annually)

2 million

Urs of Fariduddin Ganjshakar

Pakpattan, Pakistan

September 2019


Sporting events

2020 Summer Olympics

Tokyo, Japan

July 24–August 9, 2020

7.5 million

FIFA World Cup


November 21–December 18, 2022

3 million

2022 Winter Olympics

Beijing, China

February 4–20, 2022

1 million

Art and music festivals

Edinburgh Festival Fringe

Edinburgh, Scotland

August 2–26, 2019

2.5 million

Street Parade

Zurich, Switzerland

2nd Saturday in August

1 million

Health Concerns Related to Mass Gatherings

Attendance at a mass gathering can exacerbate a traveler’s existing medical conditions. Emergency medical services are often involved in preparations and are usually equipped to address acute medical conditions such as myocardial infarction and asthma. Planners usually handle conditions such as heat exhaustion, dehydration, hypothermia, or sunburn on site, as well.

Catastrophic incidents are of particular concern with mass gatherings, particularly with extremely dense crowds of people. Numerous casualties at mass gatherings have occurred as the result of poor crowd management, structural collapses, fires, and violence. Serious crush injuries and death can result from crowding and stampedes. In 2013, dozens of religious pilgrims were killed in India during a stampede at Kumbh Mela, the world’s largest mass gathering. Thousands of pilgrims were killed in a stampede at the 2015 Hajj pilgrimage in Saudi Arabia.

Personal safety during mass gatherings is important. Although the risk for large-scale incidents such as terror attacks are low, they are impossible to predict or eliminate. Travelers should be aware of their surroundings. More information is available in Chapter 3, Safety & Security Overseas.

Mass gathering attendees also are at risk for infections. Previous mass gatherings have been associated with outbreaks of influenza, meningococcal disease, and norovirus. Mass gatherings also have implications for global health security. Travelers to mass gatherings may import diseases to a host site as well as spread acquired diseases when they return home. An example was the emergence of Zika virus in 2015 in Brazil shortly before the Olympics and Paralympic Games. Visiting athletes and attendees to the Games were at risk for infection with Zika virus while attending the Games, as well as potentially exporting Zika virus to their home countries. This also posed a significant challenge to travel medicine providers, as little was known at that time about the timeline for risk to people of reproductive age.

Guidance for Clinicians

Assessing Risk

  • Ask travelers about their itineraries and activities. Verify a traveler’s itinerary to identify risks beyond those associated with the event itself. Patients may add side trips or extend travel beyond the mass gathering.
  • Consider your patient’s unique characteristics. Chronic health conditions may be exacerbated by participation in a mass gathering. Counsel patients on the importance of having adequate supplies of medication for the duration of their trip as well as documentation for any prescriptions.

Mitigating Risk

  • Identify requirements for mass gathering attendees beyond those required for entry to a country. For example, all participants in the Hajj, the Islamic pilgrimage to Mecca, require vaccination against meningococcal disease, whereas other travelers to Saudi Arabia do not.
  • Identify recommendations for attendees, as host sites may make additional recommendations based on public health concerns. After the emergence of the Middle East Respiratory Syndrome (MERS) coronavirus, Saudi Arabia recommended that elderly or immunocompromised people delay their pilgrimage.
  • Educate travelers on preventive measures. These may include things such as the regular use of insect repellent or advice on how to choose safe food and water from vendors. Educate all travelers on the importance of regular handwashing with soap and water and the use of alcohol-based sanitizer when sanitation facilities are not available.
  • Visit the CDC Travelers’ Health website at CDC regularly updates its website with travel health notices and notifications to the public of disease outbreaks in countries around the world; information may also be provided on mass gatherings such as the Hajj or Olympic Games.

Guidance for Travelers

  • Consult a travel medicine provider at least 4–6 weeks before the departure date. This should allow adequate time to receive most vaccinations. Discuss your itinerary and any planned activities with your provider so that he or she can make more accurate recommendations to ensure your health and safety. If a travel medicine provider is not locally available, a primary care provider should be able to assist you with ensuring you have the adequate vaccinations and health information necessary.
  • Register with the Department of State’s Smart Traveler Enrollment Program (STEP, Subscribe for notifications on travel warnings, travel alerts, and other information for your specific destination(s), as well as ensure that the Department of State is aware of a your presence in the event of serious legal, medical, or financial difficulties while traveling. In the event of an emergency at home, STEP can also help friends and family reach you abroad.
  • Ensure any existing medical conditions are well controlled before departure. Discuss your medical history with your medical provider during your pretravel consultation, and ensure you have an adequate supply of any prescription medications you take regularly, prior to departure.
  • Visit the CDC Travelers’ Health website at Learn more about specific destinations and view any travel notices for your destination.


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Joanna Gaines, Gary W. Brunette