Heat-Related Illnesses and Extreme Heat

Heat-related illnesses during times of extreme heat are responsible for more weather-related deaths in the United States during an average year than any other hazard. One heat wave in the 1990s claimed over 1,000 lives (Erdman, 2021).
During the last two years, the western parts of the United States, as well as Belgium, France, Germany, Luxembourg, Australia, the Netherlands, and the United Kingdom have all experienced record high temperatures and heat waves. In 2021, Siberia saw temperatures soar to 95 degrees and towns north of the Arctic Circle saw temperatures as high as 118 degrees!
Why Does This Matter?
Long-term changes in climate can directly or indirectly affect many aspects of society in potentially disruptive ways. Extreme weather events (such as heat waves and large storms) are likely to become more frequent or intense. Extreme heat can increase illnesses and deaths, especially among vulnerable populations (EPA, 2021). In areas where heat is an issue, and extreme drought and/or heat is becoming more and more common, and preventing heat-related illness and/or death is important.
What are Heat-Related Illnesses?
Heat-related illnesses can vary from a mild heat rash to fatal heat stroke. They can be categorized by the following chart (Centers for Disease Control and Prevention, [CDC], 2017).
WHAT TO LOOK FOR | WHAT TO DO |
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HEAT STROKE | |
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HEAT EXHAUSTION | |
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HEAT CRAMPS | |
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SUNBURN | |
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HEAT RASH | |
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How Can You Prevent Heat-Related Illnesses?
There are 3 main ways to prevent heat-related illnesses:
- Stay Cool
- Wear lightweight, light-colored, loose-fitting clothing.
- Stay cool indoors. Use fans or air conditioning (for temperatures over 95 degrees). Take a cool shower or bath.
- Schedule activities carefully. Rest in shady areas and limit outdoor activities to cooler times, such as early morning or evening.
- Pace yourself. Cut down on exercise in the heat. If any symptoms of heat-related illnesses appear, STOP all activity.
- Wear sunscreen. Sunburn reduces your body’s ability to cool down and can lead to dehydration. Use “broad spectrum” or “UVA/UVB protection” products.
- DO NOT LEAVE CHILDREN OR ANIMALS IN THE CAR—even if windows are cracked. Cars heat up quickly.
- Avoid eating hot or heavy meals as they add heat to the body.
- Stay Hydrated
- Drink plenty of fluids, regardless of how active you are. DO NOT wait until you are thirsty to drink.
- Avoid sugary or alcoholic drinks as they cause you to lose more fluids. Very cold drinks can cause stomach cramps.
- Replace salt and minerals.
- Keep pets hydrated. Provide plenty of fresh, cool water for pets and leave the water in a shady area.
- Stay Informed
- Check for weather updates and extreme heat alerts.
- Know the signs of heat-related illnesses and how to treat them.
- Use a buddy system so you and a co-worker (or friend) can monitor each other’s condition. If you are over 65 years of age, have a friend or relative call and check on you twice during a heat wave.
- Monitor those at high risk (including infants, young children, overweight/obese individuals, individuals who are ill from physical and/or mental health issues).

With increasing temperatures all over the world, knowing what to do during an excessive heat event can save lives.
References
Centers for Disease Control and Prevention. (2017). Tips for preventing heat-related illness. Retrieved July 8, 2021 from https://www.cdc.gov/disasters/extremeheat/heattips.html
Centers for Disease Control and Prevention. (2017). Warning signs and symptoms of heat-related illness. Retrieved July 8, 2021 from https://www.cdc.gov/disasters/extremeheat/warning.html
Environmental Protection Agency. (2021). Climate change indicators: Weather and climate. Retrieved July 9, 2021 from https://www.epa.gov/climate-indicators/weather-climate