THE scene at the hospital emergency room has been overwhelming in the past three days — humanity arriving by the hundreds in wheelchairs, stretchers or carried on shoulders or in arms; young, old, men, women, children, all swarming into the confines of an overly stretched unit. Some are disoriented or confused, some are having seizures or tremors, their limbs are stiff, eyes up — rolled, gasping for breath. Almost all have dry, parched lips and skin and body temperatures ranging from 40-42OC (104-108OF), often incompatible with life. At extreme temperatures the viscera are injured beyond repair.

This year’s heatwave in Karachi has been historical: prolonged, high temperatures, coupled with high humidity. The city was, as always, unprepared for the disaster. Power outages have been extraordinarily prolonged; water supplies have dwindled to bare trickles. And now nature has added insult to injury.

This week’s cruel heatwave has killed hundreds in Karachi. Hospitals are bursting at the seams and are closing their gates to more victims, mortuaries have no more room, and graveyards have overnight run out of burial space. The majority of mortalities are marginalised people from slums where homes are overcrowded and poorly ventilated; electricity is absent and water supply unavailable.

Two simple precautions could have saved the lives of hundreds.

The poor are usually undernourished, there is drug addiction among the youth, unhygienic conditions are the norm, making them vulnerable to infections. Hence they react adversely to uncontrollable forces of nature. Persons who have succumbed to the heatwave have mostly been daily wage earners, labourers, gardeners, housewives and the elderly.

The body has an intriguing mechanism for temperature control: the thermoregulatory centre in the hypothalamus of the brain receives signals from receptors in the skin to maintain the core temperature between 36.6-37.7OC (98-100O F). As ambient temperature rises, blood vessels in the skin dilate and heat radiates. Increased sweating and evaporation augments cooling of the body. Prolonged exposure to high temperatures, perpetuated by inadequate fluid, leads to dehydration and dysregulation of the heat control mechanism.

The earliest warning symptoms of heat exhaustion are headache, irritability, lethargy, nausea, poor appetite, dizziness and muscle cramps. If not corrected, symptoms may progress to mental confusion, disorientation, seizures, and unconsciousness. Urine flow decreases. Fever rises to 40OC (105OF) or higher, the skin is hot and dry due to absence of sweating and the pulse thin and rapid. If uncorrected, kidneys will fail, the liver, heart, lungs and brain cells are irreversibly damaged, and death ensues. Heatstroke is a medical emergency and must be prevented at all costs.

It is apparent, then, that on hot, humid days, one must take enough fluids to replace loss through excess perspiration and remain in cool and comfortable surroundings with free flow of air. Inner and outer clothes should be loose and air-permeable, the head should be covered with loosely woven material. Those working outdoors must consume extra fluid, and rest frequently in the shade. Cold showers are helpful. These simple steps are insurance against heat exhaustion and progression to heatstroke. If symptoms have advanced, the immediate remedy is to loosen all clothes, keep the patient in a cool or cold room with ice slabs, and sponge the neck, forehead, armpits, and groins with iced water. Rapid fluid replacement through intravenous drips, and if able to consume, iced drink with ORS should be enforced. Medicines to lower fever such as aspirin, paracetamol or ibuprofen should not be given as they disrupt the thermoregulatory system.

Numbers affected in the Karachi disaster have far surpassed those in upper Sindh. Cities like Jacobabad with searing summer temperatures of 50OC have had far fewer casualties than the city by the sea. Upper Sindh is accustomed to high temperatures but with low humidity, and people there are acclimatised to indigent conditions. Homes are built with high ceilings, and wind catchers on the roof; their outerwear are in keeping with hot conditions and despite having low supplies of water, they learn to conserve precious resources. Urbanisation of Karachi has led to overpopulation; homes in impoverished areas are pigeonholes with low ceilings, minimal ventilation and packed back to back.

Unquestionably, heatstroke deaths have for the first time in the history of Pakistan, earned the lexicon of a preventable public health disaster. If our meteorologists had forewarned Karachi of a heatwave, if our public health services had advised us to take just two simple precautions — drink water and stay cool, and provided the means to do so, we would not have seen these mass deaths.

After the tragic situation has taken its toll, the wringing of hands, the closure of schools and declaration of a national disaster appear pointless and hypocritical. It is already too late. Karachiites will not forget the ineptness of their rulers.

The writer is an infectious diseases specialist.

Published in Dawn, June 25th, 2015

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