Reviewing the Evidence Base for the Legacy and Benefits of Mass Gatherings: How Can We Strengthen This?

Introduction: Mass gathering (MG) events should be an opportunity to strengthen the host city/country’s public health capacity and improve compliance with the International Health Regulations (2005). This legacy should be built into the planning for the event and receive investment; the evidence to support this happening is limited. This lack of evidence on the legacy of MGs was highlighted in the recent literature review undertaken to update the Public Health for Mass Gatherings: Key Considerations (KC2) (2015). Methods: A systematic literature review methodology was used to search for relevant publications and grey literature of a wide range of MGs globally, focusing on evaluations, legacies, and impacts. This also included searches for specific technical areas, e.g., emergency response. Results: The literature review identified a small number of peer-reviewed publications that explicitly address the health legacy and evaluation from MGs or the host city/country population (11 papers met criteria from 399 identified). This makes the justification of hosting major MGs challenging. There remains a significant barrier to building and sharing the evidence base for the health legacy and benefits of hosting an MG. Linking this to legal instruments such as the IHR (2005), which requires countries to prevent, detect, and respond to public health risks, could help gain host country/city investment, as it is recognized that MGs can increase this risk. Conclusion: It was hoped that this updated literature review would identify new evidence for viable and sustainable legacies from MGs. However, the findings were limited and did not look at longer-term benefits. Legacy is often neglected due to a lack of funding, capacity, short-term thinking, and being overlooked by the focus on the smooth running of the event. Event organizers and host cities/countries should better incorporate and implement planning to reduce the risk to the event and provide sustainable legacies.