The heatwave phenomenon that has swept across Western Europe since late June 2026 has recorded an alarming death toll, surpassing 1,300 lives. A report by the World Health Organization (WHO) emphasizes that this extreme weather phenomenon is not merely ordinary discomfort, but a serious medical threat capable of incapacitating human vital organ functions.
Dr. Merita Arini, MMR, a health expert from Universitas Muhammadiyah Yogyakarta (UMY), explained that the human body has a natural thermoregulation system managed by the hypothalamus in the brain. Functioning like a thermostat, the hypothalamus works to keep the body's core temperature stable within the range of 36.5 to 37.5 degrees Celsius. Under normal conditions, the body performs blood vessel vasodilation and produces sweat to expel excess heat.
However, Dr. Merita warned that this defense mechanism has limits, especially when a heatwave is accompanied by high humidity levels. High humidity hinders the sweat evaporation process, directly impairing the body's ability to cool itself down. Consequently, core body temperature risks rising drastically out of control.
This physical damage process typically begins with severe dehydration triggering *heat exhaustion*, characterized by symptoms such as dizziness, nausea, weakness, and an increased heart rate. If not promptly addressed, this phase can progress to *heat stroke*, a medical emergency where the body's cooling system suffers complete failure.
In *heat stroke* conditions, extreme heat exposure triggers systemic inflammation that damages cells and tissues, potentially leading to organ failure and death. Given the increasing frequency of global heatwaves, health experts emphasize the importance of public literacy in recognizing the early signs of heat exhaustion to prevent fatal impacts.
