2025 has seen heat waves across Asia, Africa, North America, Europe, and the Middle East. Greece experienced one of its earliest and most intense heat waves on record, with authorities issuing several mandatory cessation of outdoor work orders1. Italy, Turkey, and Cyprus also faced soaring temperatures and wildfire risks.
Heat waves are becoming longer, more frequent, and more intense. According to the Center for Climate and Energy Solutions (C2ES), rising global temperatures are increasing the likelihood of extreme heat events, with urban areas particularly vulnerable due to the urban heat island effect.2 The frequency of multi-day heat waves has surged, and nighttime temperatures, critical for human recovery, are also rising.
The health impacts are potentially severe and growing. A recent report looking at the heat wave in Europe from 23 June to 2 July this year estimates over 2,000 died due to the heat.3,4 Extreme heat is now a major public health concern, and some have labelled it a public health emergency. Experts warn that without action, mortality rates may continue to rise. Many countries have implemented regulations to protect workers, including maximum temperature limits and workplace adaptations.
Health Implications
Heat waves can increase the strain on health and emergency services, as seen across Europe with spikes in heat-related illness admissions to hospitals. Groups particularly vulnerable to heat illness include older adults, infants, children, people with chronic health conditions, and outdoor workers. Heat stroke is the most severe form of heat illness and can be fatal. It occurs when the body is no longer able to control its temperature, and the body temperature rises rapidly. Immediate medical attention is required.
Cardiovascular and respiratory complications and kidney disease are also exacerbated by heat, with most heat-related deaths due to cardiovascular events.
Strategies to Support Your Workforce
Organisations must know their local regulations, should have conducted a risk assessment and developed a heat action plan. Illness and deaths due to heat are preventable. Measures to protect the workforce from extreme heat include:
- Putting in place a heat wave early warning system.
- Issuing heat alerts with guidance on actions to take, such as limiting outdoor activities, maintaining hydration, and taking appropriate rest breaks
- Reviewing and remediating site conditions to ensure access to shade and cooler environments.
Checklist to Address the Risks of Heat Waves
To prevent the impact of extreme temperatures on your travellers, we have created a checklist of considerations before and during a trip.
Pre-Trip
- Stay informed: Before your trip, check the local weather forecast and advice.
- Choose hotel accommodation wisely: Book accommodation with air conditioning, fans and power backup.
- Pack appropriate clothing: If the country you are travelling to has hot weather, pack loose, light-coloured clothing made of natural fabrics such as cotton or linen.
During the Trip
- Allow time for acclimatisation: Take note that children take longer to acclimatise.
- Plan your commute: Check the condition of the vehicles you are travelling in and if they have air conditioning. Never leave infants, children or pets in a parked car.
- Carry these items with you:
- Water bottle
- Hat, sunglasses and/or umbrella
- Sunscreen
- Insect repellent
- Health kit
For information on how our Health Consulting team can support your organisation in addressing health risks, click here.
- Greece Ministry of Labour & Social Security 6, 8 and 9 July 2025 https://ypergasias.gov.gr/ektakta-metra-gia-tin-antimetopisi-tis-thermikis-kataponisis-ton-ergazomenon-tou-idiotikou-tomea-tin-deftera-7-iouliou-2025/
- https://www.c2es.org/content/heat-waves-and-climate-change/
- https://www.lshtm.ac.uk/newsevents/news/2025/first-analysis-estimate-number-heatwave-deaths-linked-climate-change
- https://www.imperial.ac.uk/grantham/publications/all-publications/climate-change-tripled-heat-related-deaths-in-early-summer-european-heatwave.php