Prevention and management of heat-related illness at mass gatherings: developing evidence-based communication messages

Overview

Extreme heat is an important environmental and public health hazard. Exposure to high heat can cause heat-related illnesses and injuries and worsen underlying health conditions. The health impacts of heat are predictable and largely preventable when timely, feasible protective actions are taken by individuals, communities and organizations. As the frequency and intensity of heat events increase due to climate variability and change, organizers of major sport events and mass gatherings must transition from reactive crisis management to proactive risk mitigation.

This document provides standardized, evidence-informed content for communication messages to help prevent heat-related illnesses and injuries and mitigate heat stress during major sport events and other mass gatherings (for example, religious events, cultural events and festivals). The message content is intended to support event organizers and partners to reduce harmful heat exposure for attendees (e.g. pilgrims, spectators) as well as event organizers and staff, enable early action when heat risk increases (e.g. when forecasts or local heat alerts indicate higher risk) and strengthen on-site preparedness and response through clear, consistent public messages and staff briefings.