Hot weather is not the only condition that can lead to heat-related illness. A doctor has warned that high temperatures combined with high humidity, particularly before afternoon thunderstorms, can make it difficult for the body to cool itself even when there is no direct sunlight.
Critical care physician Dr Huang Hsuan explained that the human body mainly relies on sweat evaporation to release excess heat. However, when humidity levels are high, sweat cannot evaporate efficiently, leaving the body trapped in a “steam room” where it continues sweating without effectively lowering its temperature.
Prolonged exposure to hot and humid conditions can cause a rapid heartbeat, excessive sweating, dizziness, headaches, nausea and extreme weakness. A person’s concentration and reaction time may also be affected. In more serious cases, heat-related illness can cause muscle cramps, difficulty standing, collapse or loss of consciousness.
Importantly, Dr Huang stressed that sweating does not mean a person is safe from heatstroke. Some people suffering from severe heatstroke may continue to sweat heavily, so waiting for the skin to become dry before seeking help could be dangerous.
The most important warning signs involve changes in a person’s consciousness and behaviour. Confused speech, unusual reactions, difficulty walking, loss of direction, fainting, seizures or being unable to wake someone are all signs that severe heat-related illness may have developed.
If someone displays these symptoms, emergency medical assistance should be sought immediately. While waiting for help, move the person to a shaded or air-conditioned area, remove unnecessary clothing, wet the skin with cool water and fan the body continuously. Ice packs can also be placed around the neck, armpits and groin to help lower body temperature.
If the person is unconscious or has an altered level of consciousness, they should not be forced to drink water because of the risk of choking.
Dr Huang also reminded the public not to judge heat risk based solely on whether the sun is shining. Temperature, humidity and perceived heat all play an important role. People should drink water regularly, take adequate breaks and consider replacing electrolytes when exercising or sweating heavily.
Older adults, young children, people with heart or lung conditions, those taking diuretics and outdoor workers should take extra precautions by cooling down early and avoiding prolonged exposure to hot and humid environments.

