In the tropics, the desert or at high altitudes you can get sunburnt surprisingly quickly, even through cloud cover. Use a sunscreen , a hat
and barrier cream for your nose and lips. Calamine lotion is
a good way to soothe mild sunburn. Protect your eyes with good quality sunglasses, particularly if you will be near the sand, sun or snow.
Prickly heat is an itchy rash caused by excessive perspiration trapped under the skin. It usually strikes people who have
just arrived in a hot climate. Keeping
cool but bathing often, using a mild talcum powder or even resorting to air-conditioning may help until you acclimatise.
Dehydration and salt deficiency can cause heat exhaustion. Take time to acclimatise to high temperatures and make sure
you get sufficient liquids. Wear loose clothing and a broad-brimmed hat. Do not do anything too physically demanding.
Salt deficiency is characterised by fatigue, lethargy, headaches, giddiness and muscle cramps; salt tablets
may help, but adding extra salt to your food is better. Anhydrotic heat exhaustion, caused by an
inability to sweat, is quite rare. Unlike the other forms of heat exhaustion, it is likely to strike people who have been in a
hot climate for some time, rather than newcomers.
This serious, sometimes fatal, condition can occur if the body's heat-regulating mechanism breaks down and the body
temperature rises to dangerous levels. Long, continuous periods of exposure to high temperatures can leave you
vulnerable to heat stroke.
The symptoms are feeling unwell, not sweating very much or at all and a high body temperature (39 to 41 degrees
Celsius or 102 to 106 degrees Fahrenheit). Where sweating has ceased the skin becomes flushed and red. Severe, throbbing headaches and lack of
coordination will also occur, and the sufferer may be confused or aggressive. Eventually the victim will become delirious
or convulse.
Hospitalisation is essential, but meanwhile get victims out of the sun, remove their clothing, cover them with a wet sheet
or towel and then fan continually. Give fluids if they are conscious.
Fungal infections are occur more commonly in hot weather and are usually found on the scalp, between the toes or fingers, in the
groin and on the body (ringworm). You get ringworm (which is a fungal infection, not a worm)
from infected animals or by walking on damp areas such as shower floors.
To prevent fungal infections wear loose, comfortable clothes, avoid artificial fibres, wash frequently and dry carefully. If
you do get an infection, wash the infected area daily with a disinfectant or medicated soap and water, and rinse and dry
well. Apply an antifungal powder like tolnifate (Tinaderm). Try to expose the infected area to air or sunlight as
much as possible and wash all towels and underwear in hot water and let them dry in the sun
Too much cold is just as dangerous as too much heat, particularly if it leads to hypothermia. If you are trekking at high
altitudes or simply taking a long bus trip over mountains, particularly at night, be prepared. In some countries (eg Tibet
and Chile) you should always be prepared for cold, wet or windy conditions even if you're just out walking or hitching.
Hypothermia occurs when the body loses heat faster than it can produce it and the core temperature of the body falls. It
is surprisingly easy to progress from very cold to dangerously cold due to a combination of wind, wet clothing, fatigue
and hunger, even if the air temperature is above freezing. It is best to dress in layers; silk, wool and some of the new
artificial fibres are all good insulating materials. A hat is important, as a lot of heat is lost through the head. A strong,
waterproof outer layer is essential, as keeping dry is vital. Carry basic supplies, including food containing simple sugars
to generate heat quickly, and lots of fluid to drink. A space blanket is something all travellers in cold climates should
carry.
Symptoms of hypothermia are exhaustion, numb skin (particularly toes and fingers), shivering, slurred speech, irrational
or violent behaviour, lethargy, stumbling, dizzy spells, muscle cramps and violent bursts of energy. Irrationality may take
the form of sufferers claiming they are warm and trying to take off their clothes.
To treat mild hypothermia, first get the person out of the wind and/or rain, remove their clothing if it's wet and replace it
with dry, warm clothing. Give them hot liquids - not alcohol - and some high-kilojoule, easily digestible food. Do not rub
victims, instead allow them to slowly warm themselves. This should be enough to treat the early stages of hypothermia.
The early recognition and treatment of mild hypothermia is the only way to prevent severe hypothermia, which is a
critical condition.
Lack of oxygen at high altitudes (over 2500m) affects most people to some extent. The affect may be mild or severe and occurs because less oxygen reaches the muscles and the brain at high altitude, requiring the heart and lungs to compensate by working harder. Symptoms of Acute Mountain Sickness (AMS) usually develop during the first 24 hours at altitude but may be delayed up to three weeks. Mild symptoms include headache, lethargy, dizziness, difficulty sleeping and loss of appetite. AMS may become more severe without warning and can be fatal. Severe symptoms include breathlessness, a dry, irritative cough (which may progress to the production of pink, frothy sputum), severe headache, lack of coordination and balance, confusion, irrational behaviour, vomiting, drowsiness and unconsciousness. There is no hard-and-fast rule as to what is too high: AMS has been fatal at 3000m, although 3500 to 4500m is the usual range.
Treat mild symptoms by resting at the same altitude until recovery, usually a day or two. Paracetamol or aspirin can be taken for headaches. If symptoms persist or become worse, however, immediate descent is necessary; even 500m can help. Drug treatments should never be used to avoid descent or to enable further ascent.
The drugs acetazolamide (Diamox) and dexamethasone are recommended by some doctors for the prevention of AMS, however their use is controversial. They can reduce the symptoms, but they may also mask warning signs; severe and fatal AMS has occurred in people taking these drugs. In general we do not recommend them for travellers.
A number of measures can be adopted to prevent acute mountain sickness:
- Ascend slowly - have frequent rest days, spending two to three nights at each rise of 1,000 metres. If you reach a
high altitude by trekking, acclimatisation takes place gradually and you are less likely to be affected than if you fly directly to high altitude.
- It is always wise to sleep at a lower altitude than the greatest height reached during the day if possible. Also, once above 3000 metres, care should be taken not to increase the sleeping altitude by more than 300 metres per day.
- Drink extra fluids. The mountain air is dry and cold and moisture is lost as you breathe. Evaporation of sweat may occur unoticed and result in dehydration.
- Eat light, high-carbohydrate meals for more energy.
- Avoid alcohol as it may increase the risk of dehydration.
- Avoid sedatives.
Eating lightly before and during a trip will reduce the chances of motion sickness. If you are prone to motion sickness try
to find a place that minimises disturbance - near the wings on aircraft, close to midships on boats, near the centre on
buses. Fresh air usually helps; reading and cigarette smoke don't. Commercial antimotion-sickness preparations, which
can cause drowsiness, have to be taken before the trip commences; when you're feeling sick it's too late. Ginger (available in capsule form) and peppermint (including mint-flavoured sweets) are natural preventatives.
Jet LagThe bags are packed, you've been to all the farewell parties, then you hop on a flight of over 18
hours' duration, to the other side of the earth, with transfers increasing the travel time to what feels like two days. You
arrive at your destination not quite at your best, feeling headachey, nauseous, tired, dazed, somewhat confused and unable to
stay awake yet unable to sleep. You've even lost your appetite for all that interesting food. That's jet lag, the curse
of the 'time' traveller.
Jet lag is experienced when a person travels by air across more than three time zones (each time zone usually represents a
one-hour time difference). It occurs because many of the functions of the human body (such as temperature, pulse rate
and emptying of the bladder and bowels) are regulated by internal 24-hour cycles called circadian rhythms.
When we travel long distances rapidly, our bodies take time (usually about three days) to adjust to the 'new time' of our
destination, and we may experience fatigue, disorientation, insomnia, anxiety, impaired concentration and loss of
appetite.
The direction of travel is a major factor. Heading east will disrupt the body more than heading west. This is because
when travelling west you are essentially lengthening your `day', something your body can cope with for between 24 and 27
hours; travelling east, however, your `day' soon becomes shorter than 23 hours.
Travel stress is another factor: pre-travel parties, packing, separation from family and loss of security all take their toll.
The flight itself creates many stressors such as dehydration, poor sleep, alcohol intake and long periods of inactivity. Once at
the destination there are language, diet and climate stressors.
Ideally, you could minimise time-lag problems by sleeping and eating at times closer to the time of your destination before
you leave, but in practice this is difficult. Instead you should minimise the pain of travel by taking plenty of rest before
the flight and avoiding late nights and last-minute dashes for travellers' cheques, passport etc. Try to select flight
schedules that minimise sleep deprivation; arriving late in the day means you can go to sleep soon after you arrive. For
very long flights (especially eastbound), try to organise a stopover and also try to minimise those three-hour transit
stops.
During the flight, try to plan meals and sleep around the expected destination times. Drink plenty of water, try to exercise and
avoid taking too much alcohol. Make yourself comfortable by wearing loose-fitting clothes and perhaps bringing an eye
mask and ear plugs to help you sleep. Sleeping tablets may help regulate patterns, but be sure that they are short-acting -
you don't want to be doped-out at the airport. On arrival, stimulate your body to the new time by eating and sleeping at
the relevant local times. Exercise helps, and light walking is ideal. Many travellers report that exposure to sunlight after arrival also aids
synchronisation.
The medical world is looking at specialised hormones to ease jet lag, but this is still highly experimental. One promising
development is stimulation by intense light pulses during the flight. This appears to rapidly synchronise the brain to the
new time zone. Perhaps you may have to watch the in-flight movie, with light flashes included - a case of
feeling bad to feel better, depending on the movie being screened.
Information verified by Traveller's Medical & Vaccination Centres,
Australia
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Heat, Cold, High Altitude & Motion Sickness
Sunburn
