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Health risks during a heatwave and sweltering hot weather

An extended period of hot weather, especially when temperatures are surpassing +35 °C, it is physically challenging and presents enhanced risk for health.

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Sweltering weather, particularly in extended periods – heat waves – is uncomfortable but presents a significant health risk.

Who is most at risk?

 

Scorching hot weather is uncomfortable for most people. The following groups are particularly threatened by the very high temperatures we encounter during heat waves:

  • elderly people aged over 75 years
  • babies, young children
  • people with chronic/long-term health conditions, such as diabetes, respiratory disease, circulatory disease
  • People who are obese
  • People taking certain medicines
  • people who work outdoors, in hot/poorly ventilated areas, or engage in physical activity in hot weather
  • socially isolated people
  • people who are not acclimatized to hot weather, such as tourists from northern countries

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Always stay cool, hydrated, and healthy in scorching hot weather

 

Staying hydrated is one of the most crucial things during extreme heat. Consider taking these precautions and measures to stay healthy in scorching weather:

  • Drink plenty of water! – A human’s body cools through sweating; on a sweltering day, an adult may lose up to several liters of water. Keep drinking water, and avoid drinking alcohol, hot drinks, and drinks with high sugar content, as they can worsen dehydration. Regular water intake is a good way of preventing dehydration.
  • Keep your body cool; stay out of the sun if possible. Eat small meals, preferably fruit and salads. Wear light-colored and loose clothing made from natural materials like cotton. Take a cool shower or a cold bath if you feel hot. Also – keep your workspace and living space cool. If you do not have air conditioning, shut the curtains and blinds during the day. Stay in the coolest room, and avoid using the stove and oven as much as possible. If your home gets too hot, go to a cooler place – a library, shopping center, cinema, or swimming pool.

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  • Keep your food safe! Properly Store food that needs refrigeration! Food spoils rapidly at high temperatures, and you may risk food poisoning if it is not stored correctly.

 

  • If you need to go out in the sun, protect your skin, use proper sunscreen and clothing to avoid sunburns, and cover your head correctly.

 

  • Know your body and have a plan – Ask your doctor if you have any health conditions that may increase the risk of heat-related illness. Call and consult with your doctor if you are feeling unwell. Call emergency help (know the number!) if you feel unwell!

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Common health risks – a heat-related illnesses with symptoms: What to do if it happens?

 

WHO considers these symptoms’ descriptions and treatments below as informative only – consult with your doctor for details and professional advice:

Dehydration

 

Dehydration occurs when the body loses too much water to maintain normal functions. Symptoms include dizziness, tiredness, irritability, thirst, dark yellow urine, loss of appetite, and fainting. Drink plenty of water or diluted fruit juice. Avoid coffee, alcohol, and sugary drinks. Move to a cooler space to cool off. If you feel unwell, call your doctor or emergency room.

Heat rash

 

Heat rash is an itchy rash caused by excessive sweating. Move to a cooler, dryer environment, and keep the affected areas dry. Hydrating creams may make the condition worse. Consult with your doctor.

Heat cramps

 

This happens during strenuous activity when the body sweats and loses water and salt. Heat cramps manifest as muscle pains or spasms. If this happens, stop all activity, move/lie down in a cool place, and raise your legs slightly. Drink water or diluted juice. Have a cool shower or bath, and apply ice packs. Refrain from returning to strenuous activity for several hours. If heat cramps do not subside, seek medical help.

Heat exhaustion

 

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Heat exhaustion is a condition caused by dehydration, which causes excessive loss of water and salt. Symptoms include heavy sweating, pale skin, fast and weak pulse, fast and shallow breathing, muscle weakness or cramps, tiredness and weakness, dizziness, headache, nausea or vomiting, and fainting.

If heat exhaustion occurs, the body needs to be cooled and rehydrated by moving to a chilled place, lying down, having a cool shower or bath, and placing cool packs under the armpits, groin, or back of the neck. Rehydration should be done by taking small amounts of cool fluids. Medical help is advised if symptoms do not abate within an hour.

Heat stroke

 

Heat stroke happens when the body temperature reaches 40.5 °C, a severe and life-threatening condition! Immediate first aid in lowering body temperature is critical, and an immediate call for an ambulance! Find more information on heatstroke here.

High relative humidity during a heatwave can also significantly affect the body, making it physically challenging for those working outside. After high rainfall, intense heating helps evaporate the soaked grounds, resulting in higher humidity than usual.

We use a heat index to represent the natural feel of scorching hot temperatures and high humidity. These graphics indicate the natural feel of temperatures based on the temperature and humidity.

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As we see, when air mass has a temperature around +35 °C, humidity below 60 percent is much less challenging than once the humidity is very high, e.g., above 80 %. Thus, the actual feel temperature would be near 50 degrees Celsius.

Even at temperatures close to the 40s, such sweltering hot air becomes hard to handle with even lower humidity, 50 to 60 percent.
WHO provided images for this article.

See extreme heat events in past: