A combination of constant high temperatures and hot air have also given rise to a sudden increase in the cases of heatstroke, characterised with mild fever and acute body-ache.

Heat stroke occurs when the body's natural cooling mechanism cannot withstand the harsh weather. Normally, as the temperature rises, the body stays cool through sweating and its evaporation. When sweat is not enough to cool the body, the body temperature rises and the person develops a condition called heatstroke.

According to Dr K.K. Aggarwal, heatstroke is characterised by sudden development of low blood pressure, an increased pulse rate, confusion or coma, fits and the absence of sweating.

``If one gets affected with heat due to over exposure, the first priority should be to cool the patient immediately by removing clothes and covering the body with a wet sheet. The armpits, groin and base of the skull should be packed with cold packs'' he suggests. The next step is to fan or direct air-conditioning on the patient. As soon as possible, the patient should be shifted to the hospital where supplementary oxygen should be supplied.

The doctors advise that one should drink plenty of water before stepping outdoors. ``Drink extra water and drink less tea, coffee and alcoholic drinks which lead to dehydration. Schedule vigorous outdoor activities during cooler times of the day and take frequent breaks during outdoor activity. And avoid cooking and eating hot and heavy meals and eat plenty of fruit and fresh vegetables. Omit fatty foods and heavy desserts and wear light weight, loose fitting, light coloured clothes,'' is what they strongly recommend.

Elderly people and small children, who are especially vulnerable to the effects of heat, should take special care to shield themselves from the hot sun, the doctors say.