Heat-stroke is common in hot countries although fatalities are surprisingly rare in Thailand, according to Public Health Minister Mongkol na Songkhla.

Doctors describe heat-stroke as a form of hyperthermia, or abnor-mally elevated body temperature. It is accompanied by physical and neurological symptoms.

Unlike heat cramps and heat exhaustion - two less-severe forms of hyperthermia - heat-stroke is a true medical emergency that can be fatal if not properly and promptly treated.

Heat-stroke occurs when the body produces more heat than it can release. Each year almost 400 people in the United States die of heat-stroke.

Although there are no recorded fatalities from heat-stroke in Thailand, Mongkol warned rising temperatures from global warming would place people in this country at greater risk. The weather bureau has forecast fierce temperatures this hot season and the end of this month could see the mercury at record levels.

The higher temperatures are blamed on El Nino, the oscillation of the ocean-atmosphere system in the tropical Pacific that has seen severe drought in Thailand and extreme meteorological effects in other countries.

Common signs of its onset are the absence of perspiration and elevated body temperature, Mongkol said. Other symptoms include confusion, muscle cramps and nausea or vomiting. Victims must have their temperature lowered as soon as possible. They should be cooled with water or a chilled towel, he said. Once this has been achieved, sufferers are advised to seek medical treatment.

The elderly and young, the ill and those with high blood pressure are at greater risk. Their bodies are less able to release heat, Medical Services Department director-general Dr Chatri Banchuen said.

Even athletes and the very fit can be struck by heat-stroke. It is common in outdoor activities, Mongkol warned.

Arthit Khwankhom

The Nation