Sensible precautions

Jet lag

Anyone who’s making a long journey, especially east or west, may worry that the beginning of their trip will be spoiled by the effects of jet lag. It is caused by crossing several time zones going east or west from home. People disagree about whether travelling east or west causes the worst symptoms. Most people, but not all, prefer to travel west. This is supposed to be because the natural body rhythm settles to a slightly longer day once it is not bound by light and darkness.

Travelling directly southwards down Africa may cause fatigue from hours of travelling but involves less of the time change element that compounds the symptoms of east–west travel. Crossing time zones in a jet aircraft can land you many hours ahead of or behind home time. The fatigue of travelling is exacerbated by lost sleep plus the body’s natural rhythms being upset. No one feels like getting up at 3am and eating a large meal because that is usually rest time. It takes six days or sometimes even longer for these circadian rhythms to adapt fully, although you may feel better long before.

From time to time there are new ‘jet lag diets’ published, or new ‘cures’, which involve everything from complicated changes in sleep and meal times before travel to aromatherapy. The truth is that none of these works completely, but an understanding of the problem can reduce the suffering.

Adopting local bed and meal times helps adaptation. For long flights, it may be worth trying to book one that arrives in the early evening, so you have time to get to your hotel and then stretch your legs or take some easy relaxation shortly before bed. However, most of us choose holiday flights on the basis of dates or price rather than exact arrival time and so this may not be practical. In fact, if you arrive at your holiday destination feeling tired, this shouldn’t matter much, and isn’t really worth worrying about, although the same may not apply on a business trip. Try to allow for taking things easy in the first few days, and don’t let it bother you if you need to rest a fair bit – you’re on holiday after all!

If you’re very keen to adapt quickly, try moving your meal (and even sleep) times nearer towards those of the arrival time zone before you set off. However, by doing this, you may only shift some of the inconvenience back to home instead of experiencing it on arrival.

It is useful to reduce your sleep deprivation as much as you can. Sleeping or resting as much as possible on a long flight will help. Many travellers opt for the ‘natural’ sleep-inducing or relaxing effect of small amounts of alcohol when flying. However, long flights are dehydrating, and alcohol or strong coffee can add to the effect. Water, lots of it, makes you feel better,

especially if you’ve been drinking alcohol. Nowadays, it is considered better not to take anything that encourages sleeping slumped in one position because of the risk (small) of deep vein thrombosis (see below), so a balance between rest and moving about the cabin is necessary.

Melatonin, a new so-called ‘cure’, is available outside the UK. It is a pineal gland hormone that is naturally secreted in the evening. Bright light inhibits its production.

It appears that melatonin taken before sleep is needed works well for many people overseas who have already used it. However, further research evaluation of any long-term effects is required before it can be medically recommended.

As light naturally inhibits melatonin production, going out into sunshine or bright artificial light does seem to aid alertness. Again more research is needed into the timings and quantities of light required.

Eating protein-rich meals (which are high in a chemical called tyrosine) at breakfast and lunch may help an active day. In the evening, eating a meal with carbohydrates provides tryptophan to help natural production of the hormones necessary for sleep. Such measures often fit easily into holiday plans and may help adaptation.

The most important point is not to get too worked up about the potential for jet lag on a holiday. It may be pleasant to relax with aromatherapy or other relaxing therapies offered by the hotel on arrival and to allow your body to adapt gently. People vary enormously in their rates of adaptation. Those who really find jet lag a major problem would do better to choose holidays with short air journeys if they’re going east or west, although long flights south should pose fewer problems. If you’ve set your heart on Far East or west travel, you could consider the possibility of going by sea and road or accept that you’ll need lots of time to acclimatise if you do fly.

Deep vein thrombosis

Sitting in restricted conditions for many hours predisposes to deep vein thrombosis (DVT), just as lying immobile in a hospital bed has been recognised to cause DVT. Long distance journeys by road, as well as longer flights, have been implicated. The blood clot (which is what the DVT is) in the calf of the leg can become dangerous if particles of the clot reach the lungs; deaths have been reported, although rarely.

Although DVT in travellers is a rare condition, certain people who have the following conditions may be at slightly higher risk. These include pregnancy, those on oestrogen-containing contraceptives or HRT, obesity, some individuals with congestive heart failure, older age groups, blood disorders that increase clotting risk, previous clot, malignancy and recent surgery, especially of the abdomen and lower limbs.

Travellers can take various precautions to reduce the risk, including moving about the cabin where practicable and exercising the calf muscles while seated, so increasing the rate of blood circulation in the lower legs and discouraging pooling of blood. Travel socks help to fulfil the same function. Keeping well hydrated by drinking lots of soft drinks may possibly reduce risk and certainly makes you feel better. Some people who have no bleeding tendencies, ulcers or other contraindications to aspirin like to take one on the day of a long-haul flight; however, aspirin is more effective at reducing the risk of clots in arteries than in veins and is no longer recommended specifically for travel. The risk accumulates for those people with more than one factor and, therefore, it is sensible to seek advice from your doctor before travel. A few travellers will be advised to take anticoagulant therapy.

Safe sun

There has been a lot of publicity recently about the dangers of sunlight even in the UK. The number of cases of skin cancer has almost tripled since the early 1980s and increased exposure to sunlight has been implicated as one cause. Obviously the sun is much stronger in the Mediterranean and even more so in the tropics and, although no one wants to stop you enjoying the sun, you do need to take care (although some dermatologists would warn that any suntan is a sign of skin damage).

• Limit the amount of time that you spend out in the sun, especially at first and around the middle of the day.
• Choose cover-up clothes and get everyone to wear a broad-brimmed hat. This is particularly important if your skin is the type that burns easily and for babies and children. It appears that sunburn under age 15 years may be an important risk factor for skin cancer later on. For people with brown or black skin the risk of sun-induced skin cancer is minimal.
• Choose a sunscreen that filters out both UVA and UVB rays. The sun protection factor (SPF) number on the packaging gives an indication of the time that you should be able to spend in the sun without burning. If you could normally be out in the sun for 20 minutes without redness, then an SPF 6 should theoretically allow 6 x 20 minutes, that is, up to two hours. This assumes that the sunscreen is reapplied after swimming and regularly in the heat about every couple of hours. An SPF of at least 15 is recommended initially.

More recently, an additional star rating of one to four has been provided on the packaging to show protection against UVA rays, which cause ageing of the skin and sometimes an allergic, itchy rash.

Apply the sunscreen liberally (most people do not apply it thickly enough) remembering vulnerable areas such as the nose, shoulders, areas not often exposed to daylight and anywhere hair is thinning.

The Australian campaign slogan of Slip, Slap, Slop sums up the essentials:

Safe sun

SLIP on a shirt SLAP on a hat SLOP on some sunscreen

Getting sunburnt early on in the holiday can spoil your enjoyment for days after, so it is worth taking care to expose your skin gradually, especially areas that are usually covered up and only exposed when wearing a swimming costume (for more on this, see ‘Common skin problems’).

Heat

Overheating in hot climates can eventually cause sunstroke or heat stroke, which could be fatal. It occurs when the body’s cooling mechanisms cannot compete with overwhelming heat and consciousness is lost. It is important to prevent anyone from getting to that stage.

The body can adapt to hotter climates but it takes time and people vary in their speed of acclimatisation. For everyone, avoidance of heat stress is the key.

It is important to move slowly, staying out of direct sunlight where possible. In sunshine, ideally the head and back of the neck should be covered and loose cotton clothes worn. Lots of mainly non-alcoholic drinks should be drunk to compensate for the sweating taking place (alcohol, strong tea and coffee cause dehydration). More sweating increases the requirement for salt, but eating normally will usually provide adequate quantities and salt tablets are not recommended. Where exercising in the heat increases the salt requirement further, a little salt can be added to the food at the table, so long as adequate fluid is being taken to maintain pale urine. Dark urine is a sign of dehydration and the best remedy is drinking as much oral rehydration mixture as you comfortably can or soft drinks.

Acclimatisation gradually conserves some salt by allowing less to be lost in sweat but fluid intake must still be maintained.

People who are suffering from heat stress may feel faint and sick with a headache and the skin may feel clammy. Later as the sweating mechanism fails, the skin may become hot and dry. Once someone feels ill from the heat, they should stay in the shade or preferably in air conditioning, and drink plenty of non-alcoholic drinks even if they don’t feel thirsty. Oral rehydration solution is ideal.

Precautions in hot climates

• Stay out of direct sunlight wherever possible
• Wear loose cotton clothes and a hat to protect from sunlight
• Drink plenty of fluids (avoiding alcohol, strong tea and coffee as these cause dehydration)
• Do not take salt tablets. If required, small amounts of salt can be added to food, so long as you drink plenty
• Avoid vigorous exercise particularly in very hot and humid weather

Heat stroke

Heat stroke is a medical emergency. Immediate cooling and medical attention are essential.

Hazards of travel in cold conditions

When planning trips to colder climates (including areas of high altitude and deserts at night) make sure that you go well prepared. Conservation of heat depends on good insulation and this is best achieved by adding layers of clothes that fit comfortably over each other. A good waterproof and windproof jacket is a valuable investment because heat loss occurs much more quickly if exposed to wind and rain. Remember to pack a warm scarf, hat, mittens and anti-glare glasses.

More serious trekkers may consider visiting a specialist outdoor clothing store where warm clothing can be purchased in lightweight materials.

It is generally well known that elderly people are more susceptible to hypothermia (a drop in body temperature that affects the body’s ability to function normally), but certain illnesses may also predispose individuals to the condition. If in any doubt consult your doctor before travel.

Before setting out on long treks plan meticulously. Let a contact know where you are going, your route and when you plan to return. Check the weather conditions and access to emergency services, and plan for any other foreseeable dangers that will help to reduce risks.

Take sufficient clothes and equipment to cope should the weather change for the worst and wear well-fitting sturdy walking boots. Hot food and drink should be taken at regular intervals en route, and make sure that you take high-calorie emergency rations with you. Avoid alcohol because this enhances heat loss and increases the risks of accidents.

Fatigue and immobility also increase the risks of hypothermia, so recognise your limitations when planning excursions and try not to be too ambitious. Don’t ignore in a fellow traveller signs of hypothermia, which can range from complaints of tiredness, stumbling and slowed speech, to uncharacteristic and sometimes aggressive behaviour.

Quick action to protect the person from further cold improves the chance of recovery. Wrap the casualty in dry clothes (making sure that the head and face are protected), and move him or her to a sheltered area, getting immediate medical help if possible. If medical help is not available, getting a colleague to re-warm the hypothermic person through his or her own body heat (by removing all clothes and lying next to the person in a sleeping bag) can be life saving. It is not sensible to take such action if this puts the other person’s life at risk. Do not attempt to warm the casualty by placing too close to a fire. If the person’s condition allows, encourage lukewarm (not hot) nourishment and drinks.

Frostnip and frostbite

Sometimes only the extremities (for example, the hands, feet, nose and ears) are affected by below-freezing temperatures, and this is known as frostnip or frostbite. Numbness and whitening of the skin are indicative of frostnip, and rewarming the affected areas by placing them in warmer areas of the body (for example, putting the numb hand under the opposite armpit) is recommended. Avoid rubbing the affected area in an attempt to warm it. To ignore these early warning signs is foolhardy.

Frostnip can progress to the much more serious condition, frostbite, with the real risk of loss of the affected part or threat to life. Immediate medical assistance must be sought to reduce the risk of gangrene and other complications.

Food and water hygiene

Most of the agents that cause food poisoning from mild tummy upsets through hepatitis A to cholera and typhoid are transmitted in the same way. Somehow, bugs excreted (usually in the faeces) from one person are eaten by someone else. It follows that good personal and food hygiene will prevent a lot of infections.

The most important precaution is to wash your hands after using the lavatory and before handling food.

Food from street vendors and hotel buffets is generally best avoided as are certain species of tropical fish, because they can give rise to poisoning even when well cooked (for example, ciguatera poisoning of barracuda and a wide range of tropical reef fish). Shellfish should be avoided unless cooked thoroughly.

Safe drinking water

Remember not to drink the tap water unless you are absolutely sure that it is safe. In areas where water may be contaminated you should also refuse ice in your drinks. Canned or bottled drinks sold under reputable brand names are available in most tourist locations. When buying bottled water, make sure that the seal is intact because it is well known that some unscrupulous vendors refill bottles with spurious water. In fact many bottles carry a notice to destroy them after use for this reason. Fizzy bottled water is less likely to have been refilled.

For those who are travelling in remote areas for prolonged periods, carrying bottled water is often not feasible. It is worth considering how you will purify water before you start your travels. There are a few options and some may be more practical than others. Whichever method you choose it is essential to use the purest water supply that you can find.

If you are able to boil your water, this is the most effective way of sterilising it. There are many different opinions on how long water should be boiled for. Most references suggest between one and five minutes (even at high altitudes) to ensure sterile water. However, most experts believe that water that has just been brought to the boil is free from organisms that cause diarrhoea. For this reason tea and coffee are usually considered safe to drink.

If boiling is not practical, water can be treated with chemicals, such as iodine or chlorine. Commercial preparations such as tincture of iodine (2–2.5 per cent), iodine tablets or chlorine tablets can be purchased from travel clinics or pharmacies before you travel. Bacteria, the most common cause of travellers’ diarrhoea, are very susceptible to treatment with chlorine and iodine. Other pathogens, for example viruses or amoebic cysts, are not destroyed as easily, and treatment with iodine tends to be more reliable than chlorine for these.

Tap water can be treated at once, but water with solids (for example, river water with weed) must be filtered first to remove the debris.

There are of course a number of different water filters on the market. Some of these incorporate disinfection as well as filtration, making the process of water purification easier. Unfortunately, claims by some manufacturers have not been verified by independent bodies and it is worthwhile taking the time to investigate such claims thoroughly. Practical issues such as weight and size of the filter and maintenance should also be considered. Some filters are very expensive.

Correct storage of water is vital to prevent recontamination. If water has been boiled, wherever possible allow it to cool in the vessel in which it was boiled. Make sure that it is well covered and that the inside and rim of any bottles used are clean, allowing consumption directly from the bottle. Although it is worth trying to reduce the risks of food- and water-borne diseases, no precautions can completely guarantee protection from symptoms. It is sensible to know how to treat diarrhoea if it occurs.

Food and water hygiene

Anywhere you suspect food hygiene standards are poor:

• Choose freshly cooked, piping hot food wherever possible and meat that is cooked through
• Avoid unpurified tap water and ice made with it
• Avoid salads
• Peel fruit
• Avoid shellfish unless thoroughly cooked
• Keep flies off food
• Avoid unpasteurised milk products
• Avoid ice cream unless from a reputable supplier

Key points

• Tummy bugs are the most common cause of ill-health on holidays; following simple advice can reduce the risks

   

• Know how to treat diarrhoea in case it occurs despite precautions

   

• Be aware of the dangers of excess sun exposure, especially in children

   

• Elderly people may be more susceptible to extremes of heat and cold