Heat-related illness at mass gatherings, such as major sporting, religious and cultural events, has become a significant public health and operational risk, affecting spectators, attendees, volunteers and workers. The World Health Organization (WHO) has published a new review of evidence with guidance showing that most of the heat-related illnesses at major events can be prevented or treated on site when timely risk management measures are put in place.

The evidence review, covering studies published between 1980 and 2025, documented nearly half a million medical encounters at mass gatherings, including more than 22,000 heat-related illnesses. However, studies also showed that when on-site medical systems are well organized, more than 90% of patients can be treated at event venues, substantially reducing demand on local hospitals and ambulance services.

“Extreme heat is an increasing threat to health, safety and operational continuity in mass gatherings, and must be addressed not only as an environmental hazard but as a core operational and governance challenge,” said Dr. Chikwe Ihekweazu, executive director, WHO Health Emergencies Program. “Protection cannot rely on individual behavior alone; by strengthening consistent risk assessment, preparedness and response, we can reduce immediate harm and support safer, more resilient event planning in a warming world.”

An estimated 63% increase in heat-related deaths have occurred since the 1990s, with an average of 546,000 deaths occurring annually between 2012 and 2021. Mass gatherings can amplify heat risks in several ways, WHO said. Long periods outdoors with exposure to heat and sun, dense crowds, limited access to safe water, travel-related stress, unfamiliarity with local climatic conditions and competing demands on health services can combine to create dangerous conditions.

According to the Intergovernmental Panel on Climate Change (IPCC), hot extremes, including heatwaves, have become more frequent and more intense across most land regions since the 1950s, mainly because of climate change. Further increases in the frequency and intensity of hot extremes are projected with every additional increment of global warming.

The findings reinforce the importance of investing in preparedness and response measures before temperatures reach dangerous levels. The most effective approaches combine multiple measures, including:

• Accessible and safe drinking water and toilets.
• Cooling infrastructure.
• Schedule adjustments.
• Crowd-flow management.
• Workforce protection measures.
• Public communication.
• Real-time surveillance.
• Well-prepared on-site medical services.

The guidance focuses on spectators, attendees, volunteers and workers. It is intended to complement WHO’s guidance on heat-health action plans as well as existing national heat-health action plans, occupational health and safety requirements, emergency preparedness arrangements and clinical guidance.

October is Cybersecurity Awareness Month, creating a timely opportunity to look at cybersecurity from a financial perspective, particularly for growing businesses that may be adding employees, vendors, payment platforms and access to company accounts faster than they are adding internal controls. Additionally, new and evolving technology, such as artificial intelligence, is accelerating the rate at which hackers can find and take advantage of weak spots in computer software and systems, according to the  Cybersecurity and Infrastructure Security Agency (CISA).

Cybercriminals look for easy targets. Businesses and organizations without basic precautions are an easier target for cyber-attacks. CISA recommended that organizations start with four essential steps to safeguard their data and enable their employees to stop attacks before they happen:

1. Teach employees to avoid phishing scams: Phishing tricks employees into opening malicious attachments or sharing sensitive information. Train staff to recognize and report suspicious activity.
2. Require strong passwords: Strong passwords are a simple but powerful way to block criminals from accessing your accounts through guessing or automated attacks. Make them mandatory for all users.
3. Require multifactor authentication (MFA): MFA adds an extra layer of security beyond passwords. Require it to make accounts significantly safer. Use phishing-resistant MFA where available.
4. Update business software: Outdated software can contain exploitable flaws. Promptly install security updates and patches to keep your systems protected. 

CISA offered additional steps to help businesses of all sizes protect themselves from cyber threats:

• Require a log-on process to access systems.
• Back up data. 
• Encrypt data. 
• Get a .gov domain if eligible.   
• Report cyber incidents to CISA.
• Have an incident response plan and use it.
• Be prepared for system disruptions.