Key Facts: Understanding the Impact of Heat on Health
In recent years, the impact of extreme heat on human health has become a growing concern. Heatwaves, which are periods of unusually hot weather lasting several days or even weeks, are becoming more frequent, intense, and prolonged due to climate change. This increase in extreme heat poses a significant risk to vulnerable populations, leading to a rise in heat-related illnesses and deaths.
According to key facts provided by the World Health Organization (WHO), heat stress is a leading cause of weather-related deaths and can exacerbate underlying health conditions such as cardiovascular disease, diabetes, mental health issues, asthma, and more. Heatstroke, a severe form of heat-related illness, is a medical emergency with a high fatality rate. The number of people exposed to extreme heat is growing exponentially worldwide, with heat-related mortality increasing significantly among individuals over 65 years of age.
Studies have shown that between 2000 and 2019, approximately 489,000 heat-related deaths occurred annually, with a significant portion in Asia and Europe. In Europe alone, an estimated 61,672 excess heat-related deaths occurred during the summer of 2022. High-intensity heatwave events can lead to a spike in acute mortality, as seen in the 2003 European heatwave where 70,000 people died, and the 2010 Russian Federation heatwave which resulted in 56,000 excess deaths.
Vulnerability to heat is influenced by various factors including age, health status, occupation, and socio-economic conditions. The negative health impacts of heat are predictable and largely preventable with specific public health policies and interventions. WHO has issued guidance for public health institutions to identify and manage extreme heat risks, emphasizing the importance of climate action, preparedness, and risk management to save lives.
The impact of heat on health is significant, with heatwaves causing rapid increases in deaths, hospitalizations, and disruptions to essential services. The strain on the human body from prolonged exposure to high temperatures can lead to heat exhaustion, heatstroke, and exacerbation of chronic health conditions. Vulnerable populations, including outdoor workers, the elderly, and those living in poor housing conditions, are particularly at risk.
To mitigate the health risks associated with extreme heat, WHO recommends a series of actions for the public to take. These include staying out of the heat, keeping homes cool, staying hydrated, protecting infants and children, and being aware of the signs of heatstroke. By following these guidelines and taking proactive measures to reduce heat exposure, individuals can protect themselves and their communities from the adverse effects of extreme heat.
In response to the growing threat of extreme heat, WHO is actively working to address climate change through initiatives like the Alliance for Transformational Change in Climate and Health (ATACH). The organization is collaborating with health sectors to develop heat action plans, early warning systems, and emergency response strategies to protect vulnerable populations from the impacts of heatwaves. By raising awareness, implementing preventive measures, and promoting adaptation strategies, WHO aims to reduce the human costs of extreme heat and safeguard public health in a changing climate.