heatstroke

Rise in body temperature caused by excessive exposure to heat. Mild heatstroke is experienced as feverish lassitude, sometimes with simple fainting; recovery is prompt following rest and replenishment of salt lost in sweat. Severe heatstroke causes collapse akin to that seen in acute shock, and is potentially lethal without prompt treatment, including cooling the body carefully and giving fluids to relieve dehydration. Death rates increase by 50% during heatwaves; heat stress is responsible for more deaths than any meteorological cause, including cyclones and floods.