Heat exhaustion and Heatstroke

Heat stroke is when the core temperature of the body rises above 40C due to prolonged heat exposure or too much physical exertion in a hot environment. Babies, the elderly and people with significant medical conditions are at higher risk. In heat stroke, the natural chemical processes of the body stop working, which can cause damage to the brain, kidneys, liver, muscles and heart. Heat stroke is a medical emergency and requires urgent treatment.

Symptoms of heat stroke include:

• Body temperature above 40 C (104F)
• Rapid breathing and raised heart rate
• Nausea and vomiting
• The skin may feel hot and dry to the touch, and may appear flushed (however, in heatstroke brought on by strenuous exercise, the skin may feel moist)
• Headache
• Confusion, slurred speech, irritability and odd behaviour
• Seizures and loss of consciousness can happen if heatstroke is left untreated.
• In small children heat stroke can cause poor feeding, irritability and lethargy. There may also be signs of dehydration such as dry nappies, reduced tears when crying, and a more prominent dip in a baby’s fontanelle (soft spot on their head).

If you think someone is suffering from heat stroke, you should call an ambulance – they need emergency medical attention. Before medical help arrives, get the person out of the hot environment (into the shade or indoors, ideally with air-conditioning). Remove excess clothing if possible and start to cool them down with water- e.g in a cold bath or shower, by applying wet towels to the body or by spraying with a garden hose. Cool packs may be applied to the armpits, groins and back of the neck. Encourage the person to drink water or oral rehydration solution, as dehydration is usually present. Medications such as anti-inflammatories are not advised.

Mosquito bites

Most of us get a small red itchy bump when a mosquito bites us, though some people get more dramatic skin reactions. This is not caused by the bite itself, but by the reaction of the body’s immune system to the mozzie’s saliva.

Mosquitos tend to bite at dusk or dawn and are more common in warm, humid or tropical conditions. Some factors seem to increase the chances of being bitten in the first place, including

• male gender
• obesity
• recent exercise
• pregnancy
• having type O blood
• if you’ve recently drunk beer
• wearing dark colours may also increase the chances, as darker colours retain more heat and may attract the mozzies.

The good news is that most people get less sensitive to mozzie bites the more they get bitten over time. Prevention is obviously the best option

• wearing loose long-sleeved light-coloured clothing if outdoors at dusk or dawn
• using insect repellent spray
• when staying in high risk areas, sleeping under a mosquito net should help (this can be pre-soaked in insect repellent)
• lighting citronella candles
• don’t leave stagnant water lying around in outdoor areas, for example at the base of flower pots or in bird-baths- mozzies reproduce in still water.

Best treatment for mozzie bites

If you do get bitten, try not to scratch the area. An antihistamine may help the itch. Topical treatments such as calamine lotion, local anaesthetic cream or mid steroid creams are available in the pharmacy and may give relief.

You should see a doctor in certain situations- e.g. if the redness around the lesion is spreading dramatically, if you develop a fever, if the lesions become painful, tender or start to form blisters, or if you feel generally unwell. If bites become infected, antibiotics may be needed.