There are over 50.8 million visits abroad by UK residents every year, of which eight million are to developing countries (Office of National Statistics, 1996). Although vaccination before travel abroad is an important preventive health measure, the main health risks are associated with behaviour when travelling (DoH, 2001).
During ascent, atmospheric pressure falls. Although aeroplane cabins are pressurised, travellers who are oxygen compromised, by chronic obstructive pulmonary disease or severe anaemia for example, may become hypoxic and require additional oxygen during the flight; oxygen must be pre-booked. During descent, pressure falls; if the Eustachian tubes are inflamed, a pressure differential may occur that leads to intense pain (barotrauma) as the eardrum is drawn inward.
The possible link between deep-vein thrombosis and air travel has had much publicity recently. Advice includes drinking non-alcoholic fluids, walking around the plane at intervals and ankle-stretching exercises. Some advisers recommend compression stockings/socks, but the benefits of taking aspirin before and during flight (every 12 hours) continue to be debated.
This is the commonest illness in travellers to developing countries and is mainly bacterial in origin. Preventive measures include:
- Using safe water for drinking and cleaning teeth. Ideally, water should be boiled. Bottled water should be sparkling because it is less likely to be supplemented by tap water
- Eating freshly cooked, piping hot food and avoiding high-risk foods such as shellfish, salads, buffet foods and milk products.
When diarrhoea occurs, management involves rehydration as the mainstay, either with commercial preparations such as Dioralyte or 1 teaspoon salt: 8 teaspoons of sugar in 1 litre of boiled water.
Loperamide can used to control symptoms but should not be used:
- For more than 48 hours
- For children under the four year of age
- If there is blood in the stools.
Antibiotics such as ciprofloxacin will reduce the severity and duration diarrhoea of travellers’ diarrhoea but may affect absorption of oral contraception.
Malaria is a dangerous tropical disease caused by a parasite transmitted by a bite from an infected female anopheles mosquito.
The UK malaria guidelines (DoH, 2001) recommend that travellers should be informed they are travelling to a malaria zone (Box 1) and be given advice on:
- Bite prevention: using insect repellents on skin, covering arms and legs after dusk, avoiding stagnant water where mosquitoes breed and sleeping under Premethrin-impregnated nets are some of the methods used to prevent bites. There is no evidence that vitamin B12 or buzzers have any effect
- Chemoprophylaxis: recommendations are outlined in the DoH Yellow Book (2001) but depend on destination, season, activities (such as safari), any contraindications in the traveller and drug resistance in the area to be visited (Table 1)
- Recognition of symptoms: medical advice should be obtained if flu-like symptoms present after travel to a malarial zone.
Accidents while travelling abroad are very common. In some developing countries, medical treatment may involve additional hazards because of poor standards and facilities. For example blood transfusions, unsterile needles and syringes can carry an HIV/hepatitis B/malaria risk.
Travel insurance is an important factor to consider, as medical care abroad can be very expensive; travellers should read the policy and exclusions carefully.
Bites and stings
Animal bites abroad should always be treated with extreme caution. In countries such as Thailand and India, rabies is endemic. Bites should be washed thoroughly under a running tap for at least five minutes, and rinsed well before applying iodine or 40% alcohol (gin or whisky is an alternative) (DoH, 2001). Medical advice on the need for rabies vaccination should be sought within 24 hours.
Wearing plastic shoes in the sea can help prevent stings from jellyfish or injuries caused by standing on sea anemones, whose spines, once embedded, are difficult to remove and can lead to severe infections.
Sun and heat
It takes days for the body to acclimatise to the intense heat of the tropics and travellers can develop heat exhaustion or heat stroke. Heat exhaustion can be treated by rest and rehydration but heat stroke will require hospital admission. Exposure to sun increases the risk of developing skin cancer.
Health education advice includes:
- Using hats, umbrellas and T-shirts
- Liberal and frequent use of high-factor sunscreen (factor 15 is adequate)
- Drinking copious non-alcoholic fluids
- Staying indoors during the hottest part of the day - a siesta after lunch is a good way to achieve this (DoH, 2001).
Casual sexual encounters abroad can result in sexually transmitted infections including hepatitis B and HIV. Condoms can provide some protection but will not make it completely safe. Condoms should be purchased in the UK before travel, as those available abroad may be of poor quality or too small to be used comfortably.
Health education leaflets, such as leaflet T6 available free from Post Offices.
- Age Concern. Tel: 020-8679 8000.
- Diabetes UK. Tel: 020-7323 1531.
- British Travel Health Association (BTHA). Tel: 0141-300 1174.
HELPLINES FOR HEALTH PROFESSIONALS
- Aventis Pasteur MSD Vaccine Information Service. Tel: 07000-766 73 847.
- PHLS Communicable Diseases Surveillance Centre (CDSC) Colindale Travel Unit. Tel: 020-8200 6868.
- Malaria Reference Laboratory, London School of Hygiene and Tropical Medicine. Tel: 020-7636 3924.
TRAVEL HEALTH EDUCATIONAL COURSES
- MSc in Travel Medicine: Glasgow. Tel: 0141-330 5617
- Postgraduate Diploma: Royal Free Hospital, London. Tel: 020-77830 2999
- Royal College of Nursing/Magister Travel Health Distance Learning. Tel: 01322-427216
- English National Board (ENB) Travel Health: Staffordshire. Tel: 01785-229 684
- Travel Medicine Course: Lancaster. Tel: 01524-384 604
- Travel Medicine short course: London School of Hygiene and Tropical Medicine (LSHTM). Tel: 020-7299 4648
- Tropical Medicine for Nurses: London School of Hygiene and Tropical Medicine (LSHTM). Tel: 020-7299 4648
Department of Health. (2001) Health Information for Overseas Travel (The Yellow Book). London: The Stationery Office.
Office of National Statistics. (1996) Travel Trends Report. London: ONS.