The World Health Organisation (WHO) has released new guidance to help governments and event organisers prevent and manage heat-related illnesses at major sporting, religious and cultural gatherings. This move comes as extreme heat poses an increasing threat to health, safety and operational continuity in mass gatherings. According to Dr Chikwe Ihekweazu, Executive Director of WHO's Health Emergencies Programme, heat-related deaths have increased by an estimated 63 per cent since the 1990s.
A WHO evidence review covering studies published between 1980 and 2025 documented nearly 500,000 medical encounters at mass gatherings, including more than 22,000 heat-related illnesses. The review found that more than 90 per cent of patients can be treated at event venues when on-site medical systems are well organised, reducing pressure on local hospitals and ambulance services. This highlights the importance of timely risk assessment, preparedness and response measures in preventing and managing heat-related illnesses.
Dr Ihekweazu emphasised that heat should be addressed not only as an environmental hazard but also as a core operational and governance challenge requiring consistent risk assessment, preparedness and response. Mass gatherings can increase heat risks through prolonged outdoor exposure, dense crowds, limited access to safe water, travel-related stress and unfamiliarity with local climatic conditions. Increasing demands on health services during major events can further compound the risks associated with extreme heat and delay access to appropriate medical care.
According to the Intergovernmental Panel on Climate Change, hot extremes, including heatwaves, have become more frequent and intense across most land regions since the 1950s, largely due to climate change. Further increases in the frequency and intensity of extreme heat are projected with every additional increment of global warming. This underscores the need for proactive measures to mitigate the effects of extreme heat at mass gatherings.
The new guidance, titled Prevention and management of heat-related illness at mass gatherings, recommends accessible safe drinking water and toilets, cooling infrastructure, schedule adjustments and effective crowd-flow management to reduce heat-related health risks. It also calls for workforce protection, public communication, real-time health surveillance and well-prepared on-site medical services as part of comprehensive event preparedness.
The guidance adopts a whole-of-event approach, recognising that venue design, transport, security, communications, water and sanitation can influence people's access to cooling and medical care. It covers the full event cycle and is designed to complement national heat-health action plans, occupational health and safety requirements, emergency preparedness arrangements and clinical guidance.
Dr Ihekweazu urged governments, event organisers and partners to integrate heat-risk management into health planning, preparedness and operations for mass gatherings worldwide. The guidance aims to support the development of effective heat-risk management strategies, ultimately reducing the risk of heat-related illnesses and deaths at mass gatherings.
Key points
- WHO releases new guidance to prevent and manage heat-related illnesses at mass gatherings.
- Extreme heat poses an increasing threat to health, safety and operational continuity in mass gatherings.
- Heat-related deaths have increased by an estimated 63 per cent since the 1990s.
