The WHO defines a mass gathering (MG) as an event attended by a sufficient number of people to strain the planning and response resources of the host community, city or country. It can either be organised such as the Olympic games, or spontaneous such as the celebrations in Madrid when Spain won the soccer world cup in South Africa. These events may be social, be of a sporting nature, have religious backgrounds or be associated with natural disasters and conflict situations. They vary in size, with the largest documented one being the Indian 2025 Kumbh Mela which attracted close to half a billion attendees over a period of 55 days. Health risks include accidents, trauma, environmental factors and infectious diseases. MG’s have been associated with superspreading events, defined as events in which an infectious disease is spread much more than usual. MG’s have been associated with outbreaks of diseases at the events, as well as the worldwide spread by returning attendees to their countries of origin. The Kumbh Mela and the Hajj have cholera outbreaks reported, and the Hajj had outbreaks of meningococcal disease and worldwide dissemination. COVID-19 and influenza have documented associations with MG’s. Effective measures can be advises to mitigate against attendees contracting infectious diseases at these events as well as preventing its spread. These include vaccinations, which in some instances have proven to be very effective. Other measures include non-pharmacological ones. Education and awareness remains paramount in such circumstances.