Insurance
Make sure that you have adequate health ­insurance.

Recommended vaccinations
Plan ahead for getting your vaccinations: some of them require more than one injection over a period of time, while others should not be given together. Note that some vaccinations should not be given during pregnancy or to people with allergies.

It is recommended that you seek medical advice at least six weeks before travel. Be aware that there is often a greater risk of disease during pregnancy and among children.

Record all vaccinations on an International Certificate of Vaccination, available from your doctor. It is a good idea to carry this as proof of your vaccinations when travelling in Cambodia.

Further reading
If you are planning on travelling in remote areas for a long period of time, you may consider taking a more detailed health guide, such as Lonely Planet's Healthy Travel: Asia & India, which is a handy pocket-sized guide packed with useful information including pre-trip planning, emergency first aid, immunisation and disease information, and what to do if you get sick on the road. Where There Is No Doctor, by David Werner, is a very detailed guide intended for those going to work in an underdeveloped country.

Lonely Planet's Travel with Children, by Cathy Lanigan, includes advice on travel health for younger children.

Required & recommended vaccinations
Vaccinations you may want to consider for a trip to Cambodia are listed here, but it is imperative that you discuss your needs with your doctor. For more details about the diseases themselves, see the individual entries later in this section.

Diphtheria and tetanus – vaccinations for these two diseases are usually combined. After an initial course of three injections (usually given in childhood), boosters are necessary every 10 years.

Hepatitis A - this vaccine provides long-term immunity after an initial injection and a booster at six to 12 months. Alternatively, an injection of gamma globulin can provide short-term protection against hepatitis A - two to six months, depending on the dose. It is reasonably effective and, unlike the vaccine, is protective immediately but, because it is a blood product, there are current concerns about its long-term safety. The hepatitis A vaccine is also available in a combined form with the hepatitis B vaccine - three injections over a six-month period are required.

Hepatitis B - travellers who should consider vaccination against hepatitis B include those on a long trip, as well as those visiting countries where there are high levels of hepatitis B infection (such as Cambodia), where blood transfusions may not be adequately screened or where sexual contact or needle sharing is a possibility. Vaccination involves three injections, with a booster at 12 months. More rapid courses are available if necessary.

Japanese B Encephalitis - consider vaccination against this disease if spending a month or longer in Cambodia, when making repeated trips or if visiting during an epidemic. It involves three injections over 30 days.

Polio - everyone should keep up-to-date with this vaccination, normally given in childhood. A booster every 10 years maintains immunity.

Rabies - vaccination should be considered by those spending a month or longer in Cambodia, especially if they are cycling, handling animals, caving or travelling to remote areas. It's also recommended for children, as they may not report a bite. Vaccination involves having three injections over 21 to 28 days. Vaccinated people who are bitten or scratched by an animal will require two booster injections of vaccine; those not vaccinated require more.

Tuberculosis - the risk of travellers contracting TB is usually very low, unless you will be living with, or closely associated with, local people. Vaccination against TB (BCG vaccine) is recommended for children and young adults who will be living in high-risk areas, including Cambodia, for three months or more.

Typhoid - vaccination against typhoid may be required if you are travelling for more than a couple of weeks in Cambodia.

Yellow Fever - a yellow fever vaccine is now the only vaccine that is a legal requirement for entry into Cambodia when coming from an infected area. This refers to a direct flight from an infected area, but there are no direct flights from Africa or South America, the most likely places of infection.

In transit
Deep vein thrombosis (DVT)
Deep vein thrombosis (DVT) occurs when blood clots form in the legs during plane flights, chiefly because of prolonged immobility. The longer the flight, the greater the risk. Though most blood clots are reabsorbed uneventfully, some may break off and travel through the blood vessels to the lungs, where they may cause life-threatening complications.

The chief symptom of DVT is swelling or pain of the foot, ankle, or calf, usually on just one side. When a blood clot travels to the lungs, it may cause chest pain and difficulty in breathing. Travellers with any of these symptoms should immediately seek medical attention.

To prevent the development of DVT on long flights, walk about the cabin, contract the leg muscles while sitting, drink plenty of fluids, and avoid alcohol.

Jet lag & motion sickness
Jet lag is experienced when a person travels by air across more than three time zones. 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. When we travel long distances rapidly, our bodies take time to adjust to the `new time' of our destination, and we may experience fatigue, disorientation, insomnia, anxiety, impaired concentration and loss of appetite. These effects will usually be gone within three days of arrival, but to minimise the impact of jet lag:

rest for a couple of days prior to date of departure.

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, try to organise a stopover.

avoid excessive eating (which bloats the stomach) and alcohol intake (which causes dehydration) during the flight. Instead, drink plenty of noncarbonated, nonalcoholic drinks such as fruit juice or water.

make yourself comfortable by wearing loose-fitting clothes and perhaps bringing an eye mask and earplugs to help you sleep.

on the flight, try to sleep at the appropriate time for the time zone to which you are travelling.

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 movement - near the wing on aircraft, close to midships on boats, near the centre on buses. Fresh air usually helps; reading and cigarette smoke don't. Ginger (available in capsule form) and peppermint (including mint-flavoured sweets) are natural preventatives of motion sickness.

While you're there
Availability & cost of health care
Self-diagnosis and treatment of health problems can be risky, so you should always seek professional medical help. Although we do give drug dosages in this section, they are for emergency use only. Correct diagnosis is vital.

An embassy, consulate or five-star hotel can usually recommend a local doctor or clinic. Antibiotics should ideally be administered only under medical supervision. Take only the recommended dose at the prescribed intervals and use the whole course, even if the illness seems to be cured earlier. Stop immediately if there are any serious reactions and don't use the antibiotic at all if you are unsure that you have the correct one. Some people are allergic to commonly prescribed antibiotics such as penicillin or sulpha drugs; carry this information (eg on a bracelet) when travelling.

The best clinics and hospitals in Cambodia are found in Phnom Penh and Siem Reap. A consultation usually costs in the region of US$20 to US$40, plus medicine. Elsewhere, facilities are more basic, although a private clinic is usually preferable to a government hospital. For serious injuries or illnesses, seek treatment in Bangkok.

Dengue
This viral disease is transmitted by mosquitoes and occurs mainly in tropical and subtropical areas of the world. There is only a small risk to travellers, except during epidemics, which are usually seasonal in Cambodia, during and just after the wet season.

Unlike the malaria mosquito, the Aedes aegypti mosquito, which transmits the dengue virus, is most active during the day and is found mainly in urban areas.

Signs and symptoms of dengue fever include a sudden onset of high fever, headache, joint and muscle pains (hence its old name, `breakbone fever') and nausea and vomiting. A rash of small red spots appears three to four days after the onset of fever. Dengue is commonly mistaken for other infectious diseases, including influenza.

Seek medical attention if you think you may be infected. A blood test can diagnose infection, but there is no specific treatment for the disease. Aspirin should be avoided, as it increases the risk of haemorrhaging, but plenty of rest is advised. Recovery may be prolonged, with tiredness lasting for several weeks. Severe complications are rare in travellers but include dengue haemorrhagic fever (DHF), which can be fatal without prompt medical treatment. DHF is thought to be a result of secondary infection due to a different strain (there are four major strains) and usually affects residents of the country rather than travellers.

There is no vaccine against dengue fever - the best prevention is to avoid mosquito bites at all times.

Fungal infections
Fungal infections occur more commonly in hot weather and are usually on the scalp, between the toes (athlete's foot) or fingers, in the groin and on the body (ringworm). Ringworm, a fungal infection, not a worm, is contracted from infected animals or other people. Moisture encourages these infections.

To prevent fungal infections wear loose, comfortable clothes, avoid artificial fibres, wash frequently and dry yourself carefully. If you do get an infection, wash the infected area at least daily with a disinfectant or medicated soap and water, and rinse and dry well. Apply an antifungal cream or powder like tolnaftate (Tinaderm). Try to expose the infected area to air or sunlight as much as possible. Wash all towels and underwear in hot water, change them often and let them dry in the sun.

Hepatitis
Hepatitis is a general term for inflammation of the liver. It is a common disease worldwide. There are several different viruses that cause hepatitis, and they differ in the way that they are transmitted. The symptoms are similar in all forms of the illness, and include fever, chills, headache, fatigue, feelings of weakness and aches and pains, followed by loss of appetite, nausea, vomiting, abdominal pain, dark urine, light-coloured faeces, jaundiced (yellow) skin and yellowing of the whites of the eyes. People who have had hepatitis should avoid alcohol for some time after the illness, as the liver needs time to recover.

Hepatitis A is transmitted by ingesting contaminated food or water. You should seek medical advice, but there is not much you can do apart from resting, drinking lots of fluids, eating lightly and avoiding fatty foods. Hepatitis E is transmitted in the same way as hepatitis A; it can be particularly serious in pregnant women.

There are almost 300 million chronic carriers of hepatitis B in the world. It is spread through contact with infected blood, blood products or body fluids; for example, through sexual contact, unsterilised needles, blood transfusions or contact with blood via small breaks in the skin. Other risk situations include shaving, tattooing or body piercing with contaminated equipment. The symptoms of hepatitis B may be more severe than type A and the disease can lead to long-term problems such as chronic liver damage, liver cancer or a long-term carrier state. Hepatitis C and D are spread in the same way as hepatitis B and can also lead to long-term complications.

There are vaccines against hepatitis A and B, but there are currently no vaccines against the other types of hepatitis. Following the basic rules about food and water (hepatitis A and E) and avoiding risk situations (hepatitis B, C and D) are important preventative measures.

HIV/AIDS
Infection with the human immunodeficiency virus (HIV) may lead to acquired immune deficiency syndrome (AIDS), which is a fatal disease. Any exposure to blood, blood products or body fluids may put the individual at risk.

The disease is often transmitted through sexual contact or dirty needles, so vaccinations, acupuncture, tattooing and body piercing can be potentially as dangerous as intravenous drug use. HIV/AIDS can also be spread through infected-blood transfusions; although the blood centre in Phnom Penh does screen blood used for transfusions, it is unlikely to be done in many of the provinces.

If you do need an injection, ask to see the syringe unwrapped in front of you, or take a needle and syringe pack with you. Fear of HIV infection should never preclude any treatment for serious medical conditions.

According to WHO figures, Cambodian rates of infection are highest among sex workers. However, due to a concerted awareness campaign, HIV/AIDS infection rates have been steadily declining in the past decade from a high of around 5% of the population in the 1990s to about 1.6% today.

Intestinal worms
These parasites are most common in rural Cambodia. The various worms have different ways of infecting people. Some may be ingested in food such as undercooked meat (eg tapeworms) and some enter through your skin (eg hookworms). Infestations may not show up for some time, and although they are generally not serious, if left untreated they may cause severe health problems later. Consider having a stool test when you return home to check for worms to determine the appropriate treatment.

Japanese B encephalitis
This viral infection of the brain is transmitted by mosquitoes. Most cases occur among locals living in rural areas, as the virus exists in pigs and wading birds. Symptoms include fever, headache and alteration in consciousness. Hospitalisation is needed for correct diagnosis and treatment. There is a high mortality rate among those who have symptoms; of those who survive many are intellectually disabled.

Malaria
This serious and potentially fatal disease is spread by mosquitoes. If you are travelling in endemic areas it is extremely important to avoid mosquito bites and to take tablets to prevent the disease developing if you become infected. There is no malaria in Phnom Penh, Siem Reap and most other major urban areas in Cambodia, so visitors on short trips to the most popular places do not need to take medication. Malaria self-test kits are widely available in Cambodia, but are not that reliable.

Symptoms of malaria include fever, chills and sweating, headache, aching joints, diarrhoea and stomach pains, usually preceded by a vague feeling of ill health. Seek medical help immediately if malaria is suspected, as, without treatment, the disease can rapidly become more serious or even fatal.

If medical care is not available, malaria tablets can be used for treatment. You need to use a different malaria tablet to the one you were taking when you contracted the disease, as obviously the first type didn't work. If travelling widely in rural areas of Cambodia, it is worth visiting a pharmacy to purchase a treatment dose - this will save you from complications in the event of an emergency. Antimalarials are available cheaply throughout Cambodia, although buy them from a reputable clinic to be sure they are not fakes.

Travellers are advised to prevent mosquito bites at all times. The main messages:

Wear light-coloured clothing.

Wear long trousers and long-sleeved shirts.

Use mosquito repellents containing the compound DEET on exposed areas (prolonged overuse of DEET may be harmful, especially to children, but its use is considered preferable to being bitten by disease-transmitting ­mosquitoes).

Avoid perfumes or aftershave.

Use a mosquito net impregnated with mosquito repellent (permethrin) - it may be worth taking your own.

Impregnate clothes with permethrin to effectively deter mosquitoes and other insects.

Malaria medication
Antimalarial drugs do not prevent you from being infected but they kill the malaria parasites during their developmental stage, significantly reducing the risk of becoming very ill or dying. Expert advice on medication should be sought, as there are many factors to consider, including the area to be visited, the risk of exposure to malaria-carrying mosquitoes, the side effects of medication, your medical history and whether you are a child or an adult, and whether you’re pregnant. Travellers heading to isolated areas in Cambodia should carry a treatment dose of medication for use if symptoms occur. A new drug called Malarine, supplied and subsidised by the European Union (EU) and WHO, is cheaply available in pharmacies throughout Cambodia. A combination of artesunate and mefloquinine, it is undoubtedly the most effective malaria killer available in Cambodia today. See the English instructions for advice about the appropriate dosage.

Schistosomiasis
Also known as bilharzia, this disease is transmitted by minute worms. They infect certain varieties of freshwater snails found in rivers, streams, lakes and, in particular, dams. The worms multiply and are eventually discharged into the water.

The worm enters through the skin and attaches itself to the intestines or bladder. The first symptom may be feeling generally unwell, or a tingling and sometimes a light rash around the area where the worm entered. Weeks later a high fever may develop. Once the disease is established, abdominal pain and blood in the urine are other signs. The infection often causes no symptoms until the disease is well established (several months to years after exposure), when damage to internal organs is irreversible.

The main method of preventing the disease is avoiding swimming or bathing in fresh water where bilharzia is present. Even deep water can be infected. If you do get wet, dry off quickly and dry your clothes as well.

A blood test is the most reliable way to diagnose the disease, but the test will not show positive until a number of weeks after exposure.

Sexually transmitted infections (STIs)
Gonorrhoea, herpes and syphilis are among these infections. Sores, blisters or a rash around the genitals and discharges or pain when urinating are common symptoms. With some STIs, such as wart virus or chlamydia, symptoms may be less marked or not observed at all, especially in women. Syphilis symptoms eventually disappear completely, but the disease continues and can cause severe problems in later years. While abstinence from sexual contact is the only 100% effective prevention, using condoms is also effective. Reliable condoms are widely available throughout urban areas of Cambodia. Different STIs each require specific antibiotics. The treatment of gonorrhoea and syphilis is with antibiotics. There is no cure for herpes or HIV/AIDS.

Typhoid
Typhoid fever is a dangerous gut infection caused by contaminated water and food. Medical help must be sought.

In its initial stages sufferers may feel they have a bad cold or flu on the way, as early symptoms are a headache, body aches and a fever that rises a little each day until it is around 40°C (104°F) or higher. The victim’s pulse is often slow relative to the degree of fever present - unlike a normal fever where the pulse increases. There may also be vomiting, abdominal pain, diarrhoea or constipation.

In the second week the high fever and slow pulse continue, and a few pink spots may appear on the body; trembling, delirium, weakness, weight loss and dehydration may occur. Complications such as pneumonia, perforated bowel or meningitis may also present themselves.

Traveller's diarrhoea
Simple things like a change of water, food or climate can all cause a mild bout of diarrhoea, but a few rushed toilet trips with no other symptoms are not indicative of a major problem. Almost everyone gets a mild bout of the runs on a longer visit to Cambodia.

Dehydration is the main danger with diarrhoea, particularly in children or the elderly as dehydration can occur quite quickly. Under all circumstances fluid replacement is the most important thing to remember. Weak black tea with a little sugar, soda water, or soft drinks allowed to go flat and diluted 50% with clean water are all good. You need to drink at least the same volume of fluid that you are losing in bowel movements and vomiting. Urine is the best guide to the adequacy of replacement: if you have small amounts of concentrated urine, you need to drink more. Keep drinking small amounts often. Stick to a bland diet as you recover.

With severe diarrhoea, a rehydrating solution is preferable to replace lost minerals and salts. Commercially available oral rehydration salts are very useful; add them to boiled or bottled water. In an emergency you can make up a solution of six teaspoons of sugar and a half-teaspoon of salt to a litre of boiled or bottled water.

Gut-paralysing drugs such as Lomotil or Imodium can be used to bring relief from the symptoms of diarrhoea, although they do not actually cure the problem. Only use these drugs if you do not have access to toilets and must travel. For children under 12 years the use of Lomotil and Imodium is not recommended. Do not use these drugs if the person has a high fever or is severely dehydrated.

In certain situations antibiotics may be required: diarrhoea with blood or mucus (dysentery), any diarrhoea with fever, profuse watery diarrhoea, persistent diarrhoea not improving after 48 hours and severe diarrhoea. These suggest a more serious cause of diarrhoea, and gut-paralysing drugs should be avoided.

In these situations, a stool test may be necessary to diagnose what bug is causing the diarrhoea, so seek medical help urgently. Where this is not possible the recommended drugs for bacterial diarrhoea - the most likely cause of severe diarrhoea in travellers - are norfloxacin (400mg twice daily for three days) or ciprofloxacin (500mg twice daily for five days). These are not recommended for children or pregnant women. The drug of choice for children would be co-trimoxazole (Bactrim, Septrin or Resprim) with dosage dependent on weight. A five-day course of the drug is given. Ampicillin or amoxycillin may be given in pregnancy, but medical care is necessary.

Amoebic dysentery & giardiasis
Two other causes of persistent diarrhoea in travellers are amoebic dysentery and giardiasis.

Amoebic dysentery, caused by the protozoan Entamoeba histolytica, is characterised by a gradual onset of low-grade diarrhoea, often with blood and mucus. Cramping abdominal pain and vomiting are less likely than in other types of diarrhoea, and fever may not be present. Amoebic dysentery will persist until treated and can recur and cause other health problems.

Giardiasis is caused by a common parasite, Giardia lamblia. Symptoms include stomach cramps, nausea, a bloated stomach, watery, foul-smelling diarrhoea and frequent gas. Giardiasis can appear several weeks after you have been exposed to the parasite. The symptoms may disappear for a few days and then return; this can go on for several weeks.

Seek medical advice if you think you have giardiasis or amoebic dysentery, but where this is not possible, tinidazole (Fasigyn) or metronidazole (Flagyl) are the recommended drugs to take, although the side effects of Flagyl are severe. Treatment is a 2g single dose of Fasigyn or 250mg of Flagyl three times daily for five to 10 days.

Food
There is an old adage that says `If you can cook it, boil it or peel it you can eat it…otherwise forget it'. This is slightly extreme, but many travellers have found it is better to be safe than sorry. Vegetables and fruit should be washed with purified water or peeled where possible. Beware of ice cream that is sold in the street or anywhere it might have been melted and refrozen. Shellfish such as mussels, oysters and clams should be avoided, as should undercooked meat, particularly in the form of mince. Steaming does not make shellfish safe for eating.

If a place looks clean and well run, and the vendor also looks clean and healthy, then the food is probably safe. In general, places that are packed with travellers or locals will be fine, while empty restaurants might be empty for a reason. The food in busy restaurants is cooked and eaten quite quickly with little standing around and is probably not reheated.

Water
The number one rule is be careful of the water and ice, even though both are almost always factory-produced, a legacy of the French. If you don't know for certain that the water is safe, assume the worst. Reputable brands of bottled water or soft drinks are generally fine, but you can't safely drink tap water. Only use water from containers with a serrated seal. Tea and coffee are generally fine, as the water will have been boiled.

The simplest way of purifying water is to boil it thoroughly. Vigorous boiling should be satisfactory; however, at high altitude water boils at a lower temperature, so germs are less likely to be killed. Make sure you boil it for longer in these environments.

Consider purchasing a water filter for a long trip. Total filters take out all parasites, bacteria and viruses and make water safe to drink. They are often expensive, but can be more cost effective than buying bottled water. Simple filters (which can even be a nylon mesh bag) take out dirt and larger foreign bodies from the water so that chemical solutions work much more effectively; if the water is dirty, chemical solutions may not work at all. Chlorine tablets (Puritabs, Steritabs or other brands) will kill many pathogens, but not some parasites like giardia and amoebic cysts. Iodine is more effective in purifying water and is available in tablet form (such as Potable Aqua).

Gynaecological problems
Antibiotic use, synthetic underwear, sweating and contraceptive pills can lead to fungal vaginal infections, especially when travelling in hot climates. Thrush (yeast infection or vaginal candidiasis) is characterised by a rash, itching and discharge. Nystatin, miconazole or clotrimazole pessaries or vaginal cream are the usual treatment. Maintaining good personal hygiene and wearing loose-fitting clothes and cotton underwear may help prevent these infections.

STIs are a major cause of vaginal problems. Symptoms include a smelly discharge, painful intercourse and sometimes a burning sensation when urinating. Medical attention should be sought and male sexual partners must also be treated. Besides abstinence, the best thing is to practise safe sex using condoms.

Pregnancy
Most miscarriages occur during the first three months of pregnancy. Miscarriage is common and can occasionally lead to severe bleeding. The last three months of pregnancy should also be spent within reasonable distance of good medical care. A baby born as early as 24 weeks stands a chance of survival, but only in a good modern hospital such as Calmette in Phnom Penh. Pregnant women should avoid all unnecessary medication, although vaccinations and malarial prophylactics should still be taken where needed. Additional care should be taken to prevent illness and particular ­attention should be paid to diet and nutrition.