Inoculations for trekking
It's exciting to trek in remote regions of developing countries. However, you are also far away from reliable medical care in an environment that can severely challenge your health. Endemic problems include a variety of water born diseases, hook worm, malaria, bilhazia, poor sanitation, fleas, flies, ticks and leeches. A few preventive measures before you go and an awareness of the problems can help reduce the risks to health.
Immunisation for yellow fever is compulsory for some countries and a certificate of vaccination is required
Visit your GP and ask for 'The Travellers Guide to Health' booklet (also available at most travel agents). The Expedition Advisory Centre at the Royal Geographical Society produces notes and advice specific to the country you want to visit, and the Foreign and Commonwealth Office keeps their website up-to-date with all the latest medical and political information that you will need.
Immunisation for yellow fever is compulsory for some countries and a certificate of vaccination is required in your passport. Otherwise the whole issue of immunisation against disease is a highly controversial subject. There is no guarantee that injections against tetanus, cholera, hepatitis or any of the many foreign and water borne diseases are effective. If you do decide to go ahead with immunisations, they may require a follow up visit - so leave time for these, and time to recover from any after effects, before you leave. British Airways operates a travel clinic, which can provide immunisation and advice health advice for travellers.
If you decide to take anti-malaria tablets, they must be taken at least one week before you leave. This allows time to see if the tablets have any unacceptable side effects - and if so, there is time to change to another type. You will need to take them throughout your stay in the malaria area and for a full four weeks after your return. Whilst anti-malaria drugs greatly reduce the risk, they are never 100% effective against the disease. The best prevention is to avoid being bitten. You can only catch malaria from the bite of an infected mosquito. No bites means no malaria. Wear long sleeved shirts in the evening and cover as much skin as possible. If you develop 'flu like symptoms, even several weeks after returning home, see your doctor immediately and mention that you have recently been in a malaria region. At present, you cannot donate blood if you have visited such a region.
Some essential oils such as eucalyptus, lavender or citronella (dilute a few drops in a base massage oil) are an alternative to the poisonous DEET based insect repellents and, for some people, increasing your vitamin B1 intake is a surprisingly effective insect deterrent too.
If bitten, use an anti-histamine based cream or Tiger Balm (both available from Boots the Chemist. Tiger Balm is sold everywhere in Kathmandu!)
Keep up your fluid intake - make sure that your water supply is 'clean'. In remote areas you may need to purify your own water, but most organised trips will take you through places where bottled water is available. Take a supply of the rehydration fluid Dioralyte. It comes as a powder in sachets or tablets and is very effective in preventing dehydration from excessive diarrhoea.