Traveller's diarrhoea

What is traveller's diarrhoea?

Traveller's diarrhoea is diarrhoea that develops during, or shortly after, travel abroad. Diarrhoea is defined as: 'loose or watery stools (faeces), usually at least three times in 24 hours.'

What causes traveller's diarrhoea?

Traveller's diarrhoea is caused by eating food, or drinking water, containing certain germs (microbes) or their poisons (toxins). The types of germs which may be the cause include:

• Bacteria: these are the most common microbes that cause traveller's diarrhoea. Common types of bacteria involved are:

  • Escherichia coli

  • Campylobacter

  • Salmonella

  • Shigella

• Viruses: these are the next most common, particularly norovirus and rotavirus.

• Parasites: these are less common causes. Giardia, cryptosporidium and Entamoeba histolytica are examples of parasites that may cause traveller's diarrhoea.

Often the exact cause of traveller's diarrhoea is not found and studies have shown that in many people no specific microbe is identified despite testing (for example, of a stool (faeces) specimen).

See the separate leaflets called E. Coli (VTEC O157), Campylobacter, Salmonella, Cryptosporidium, Amoebiasis (dysentery information), Shigella and Giardia for more specific details on each of the microbes mentioned above.

Are all travellers at risk?

Traveller's diarrhoea most commonly affects people who are travelling from a developed country, such as the UK, to a developing country where sanitation and hygiene measures may not meet the same standards. It can affect as many as 2 to 6 in 10 travellers.

There is a different risk depending on whether you travel to high-risk areas or not:

High-risk areas: South and Southeast Asia, Central America, West and North Africa, South America, East Africa.

Medium-risk areas: Russia, China, Caribbean, South Africa.

Low-risk areas: North America, Western Europe, Australia and New Zealand.

Sometimes outbreaks of diarrhoea can occur in travellers staying in one hotel or, for example, those staying on a cruise ship. People travelling in more remote areas (for example, trekkers and campers) may also have limited access to medical care if they do become unwell.

What are the symptoms of traveller's diarrhoea?

By definition, diarrhoea is the main symptom. This can be watery and can sometimes contain blood. Other symptoms may include:

• Crampy tummy (abdominal) pains.

• Feeling sick (nausea).

• Being sick (vomiting).

• A high temperature (fever).

Symptoms are usually mild in most people and last for 3 to 4 days but they may last longer. Symptoms may be more severe in the very young, the elderly, and those with other health problems. Those whose immune systems are not working as well as normal are particularly likely to be more unwell. For example, people with untreated HIV infection, those on chemotherapy, those on long-term steroid treatment or those who are taking drugs which suppress their immune system, for example after a transplant or to treat an autoimmune condition

Despite the fact that symptoms are usually fairly mild, they can often mean that your travel itinerary is interrupted or may need to be altered.

How is traveller's diarrhoea diagnosed?

Traveller's diarrhoea is usually diagnosed by the typical symptoms. As mentioned above, most people have mild symptoms and do not need to seek medical advice. However, in some cases medical advice is needed (see below).

If you do see a doctor, they may suggest that a sample of your stool (faeces) be tested. This will be sent to the laboratory to look for any microbes that may be causing your symptoms. Sometimes blood tests or other tests may be needed if you have more severe symptoms or develop any complications.

When should I seek medical advice for traveller's diarrhoea?

As mentioned above, most people with traveller's diarrhoea have relatively mild symptoms and can manage these themselves by resting and making sure that they drink plenty of fluids. However, you should seek medical advice in any of the following cases, or if any other symptoms occur that you are concerned about:

• If you have a high temperature (fever).

• If you have blood in your stools (faeces).

• If it is difficult to get enough fluid because of severe symptoms: frequent or very watery stools or repeatedly being sick (vomiting).

• If the diarrhoea lasts for more than 5-7 days.

• If you are elderly or have an underlying health problem such as diabetes, inflammatory bowel disease, or kidney disease.

• If you have a weakened immune system because of, for example, chemotherapy treatment, long-term steroid treatment, or HIV infection.

• If you are pregnant.

• If an affected child is under the age of 6 months.

• If you develop any of the symptoms listed below that suggest you might have lack of fluid in your body (dehydration). If it is your child who is affected, there is a separate list for children.

Symptoms of dehydration in adults

• Tiredness.

• Dizziness or light-headedness.

• Headache.

• Muscle cramps.

• Sunken eyes.

• Passing less urine.

• A dry mouth and tongue.

• Weakness.

• Becoming irritable.

Symptoms of severe dehydration in adults

• Profound loss of energy or enthusiasm (apathy).

• Weakness.

• Confusion.

• A fast heart rate

• Producing very little urine.

• Coma, which may occur.

Symptoms of dehydration in children

• Passing little urine.

• A dry mouth.

• A dry tongue and lips.

• Fewer tears when crying.

• Sunken eyes.

• Weakness.

• Being irritable.

• Having a lack of energy (being lethargic).

Symptoms of severe dehydration in children

• Drowsiness.

• Pale or mottled skin.

• Cold hands or feet.

• Very few wet nappies.

• Fast (but often shallow) breathing.

Dehydration is more likely to occur in:

• Babies under the age of 1 year (and particularly those under 6 months old). This is because babies don't need to lose much fluid to lose a significant proportion of their total body fluid.

• Babies under the age of 1 year who were a low birth weight and who have not caught up with their weight.

• A breastfed baby who has stopped being breastfed during their illness.

• Any baby or child who does not drink much when they have a gut infection (gastroenteritis).

• Any baby or child with severe diarrhoea and vomiting. (For example, if they have passed five or more diarrhoeal stools and/or vomited two or more times in the previous 24 hours.)

How is traveller's diarrhoea in adults treated?

In most cases, specific treatment of traveller's diarrhoea is not needed. The most important thing is to make sure that you drink plenty of fluids to avoid lack of fluid in your body (dehydration).

Fluid replacement

• As a rough guide, drink at least 200 mls after each watery stool (bout of diarrhoea).

• This extra fluid is in addition to what you would normally drink. For example, an adult will normally drink about two litres a day but more in hot countries. The above '200 mls after each watery stool' is in addition to this usual amount that you would drink.

• If you are sick (vomit), wait 5-10 minutes and then start drinking again but more slowly. For example, a sip every 2-3 minutes but making sure that your total intake is as described above.

• You will need to drink even more if you are dehydrated. A doctor will advise on how much to drink if you are dehydrated.

For most adults, fluids drunk to keep hydrated should mainly be water. However, this needs to be safe drinking water - for example, bottled, or boiled and treated water. It is best not to have drinks that contain a lot of sugar, such as fizzy drinks, as they can sometimes make diarrhoea worse. Alcohol should also be avoided.

Rehydration drinks

Rehydration drinks may also be used. They are made from sachets that you can buy from pharmacies and may be a sensible thing to pack in your first aid kit when you travel. You add the contents of the sachet to water.

Home-made salt/sugar mixtures are used in developing countries if rehydration drinks are not available; however, they have to be made carefully, as too much salt can be dangerous. Rehydration drinks are cheap and readily available in the UK, and are the best treatment. Note that safe drinking water should be used to reconstitute oral rehydration salt sachets.

Antidiarrhoeal medication

Antidiarrhoeal medicines are not usually necessary or wise to take when you have traveller's diarrhoea. However you may want to use them if absolutely necessary - for example, if you will be unable to make regular trips to the toilet due to travelling.You can buy antidiarrhoeal medicines from pharmacies before you travel. The safest and most effective is loperamide.

The adult dose of this is two capsules at first. This is followed by one capsule after each time you pass some diarrhoea up to a maximum of eight capsules in 24 hours. It works by slowing down your gut's activity.

You should not take loperamide for longer than two days. You should also not use antidiarrhoeal medicines if you have a high temperature (fever) or bloody diarrhoea.

Eat as normally as possible

It used to be advised to 'starve' for a while if you had diarrhoea. However, now it is advised to eat small, light meals if you can. Be guided by your appetite. You may not feel like food and most adults can do without food for a few days. Eat as soon as you are able but don't stop drinking. If you do feel like eating, avoid fatty, spicy or heavy food. Plain foods such as bread and rice are good foods to try eating.

Antibiotic medicines

Most people with traveller's diarrhoea do not need treatment with antibiotic medicines. However, sometimes antibiotic treatment is advised. This may be because a specific germ (microbe) has been identified after testing of your stool (faeces) sample.

How is traveller's diarrhoea in children treated?

Fluids to prevent dehydration

You should encourage your child to drink plenty of fluids. The aim is to prevent lack of fluid in the body (dehydration). The fluid lost in their sick (vomit) and/or diarrhoea needs to be replaced. Your child should continue with their normal diet and usual drinks. In addition, they should also be encouraged to drink extra fluids. However, avoid fruit juices or fizzy drinks, as these can make diarrhoea worse.

Babies under 6 months old are at increased risk of dehydration. You should seek medical advice if they develop acute diarrhoea. Breast feeds or bottle feeds should be encouraged as normal. You may find that your baby's demand for feeds increases. You may also be advised to give extra fluids (either water or rehydration drinks) in between feeds.

If you are travelling to a destination at high risk for traveller's diarrhoea, you might want to consider buying oral rehydration sachets for children before you travel. These can provide a perfect balance of water, salts and sugar for them and can be used for fluid replacement. Remember that, as mentioned above, safe water is needed to reconstitute the sachets.

If your child vomits, wait 5-10 minutes and then start giving drinks again but more slowly (for example, a spoonful every 2-3 minutes). Use of a syringe can help in younger children who may not be able to take sips.

Fluids to treat dehydration

If your child is mildly dehydrated, this may be treated by giving them rehydration drinks. A doctor will advise about how much to give. This can depend on the age and the weight of your child. If you are breastfeeding, you should continue with this during this time. It is important that your child be rehydrated before they have any solid food.

Sometimes a child may need to be admitted to hospital for treatment if they are dehydrated. Treatment in hospital usually involves giving rehydration solution via a special tube called a 'nasogastric tube'. This tube passes through your child's nose, down their throat and directly into their stomach. An alternative treatment is with fluids given directly into a vein (intravenous fluids).

Eat as normally as possible once any dehydration has been treated

Correcting any dehydration is the first priority. However, if your child is not dehydrated (most cases), or once any dehydration has been corrected, then encourage your child to have their normal diet. Do not 'starve' a child with infectious diarrhoea. This used to be advised but is now known to be wrong. So:

• Breastfed babies should continue to be breastfed if they will take it. This will usually be in addition to extra rehydration drinks (described above).

• Bottle-fed babies should be fed with their normal full-strength feeds if they will take it. Again, this will usually be in addition to extra rehydration drinks (described above). Do not water down the formula, or make it up with less water than usual. This can make a baby very ill.

• Older children - offer them some food every now and then. However, if he or she does not want to eat, that is fine. Drinks are the most important consideration and food can wait until the appetite returns.

Medication

Loperamide is not recommended for children with diarrhoea. There are concerns that it may cause a blockage of the gut (intestinal obstruction) in children with diarrhoea.

Most children with traveller's diarrhoea do not need treatment with antibiotics. However, for the same reasons as discussed for adults above, antibiotic treatment may sometimes be advised in certain cases.

Side-effects of traveller's diarrhoea

Most people have mild illness and complications of traveller's diarrhoea are rare. However, if complications do occur, they can include the following:

Salt (electrolyte) imbalance and dehydration.

This is the most common complication. It occurs if the salts and water that are lost in your stools (faeces), or when you are sick (vomit), are not replaced by you drinking adequate fluids. If you can manage to drink plenty of fluids then dehydration is unlikely to occur, or is only likely to be mild and will soon recover as you drink.

Severe dehydration can lead to a drop in your blood pressure. This can cause reduced blood flow to your vital organs. If dehydration is not treated, your kidneys may be damaged. Some people who become severely dehydrated need a 'drip' of fluid directly into a vein. This requires admission to hospital. People who are elderly or pregnant are more at risk of dehydration.

Reactive complications

Rarely, other parts of your body can 'react' to an infection that occurs in your gut. This can cause symptoms such as joint inflammation (arthritis), skin inflammation and eye inflammation (either conjunctivitis or uveitis). Reactive complications are uncommon if you have a virus causing traveller's diarrhoea.

Spread of infection

The infection can spread to other parts of your body such as your bones, joints, or the meninges that surround your brain and spinal cord. This is rare. If it does occur, it is more likely if diarrhoea is caused by salmonella infection.

Irritable bowel syndrome

Irritable bowel syndrome is sometimes triggered by a bout of traveller's diarrhoea.

Lactose intolerance

Lactose intolerance can sometimes occur for a period of time after traveller's diarrhoea. It is known as 'secondary' or 'acquired' lactose intolerance. Your gut (intestinal) lining can be damaged by the episode of diarrhoea. This leads to lack of a substance (enzyme) called lactase that is needed to help your body digest the milk sugar lactose.

Lactose intolerance leads to bloating, tummy (abdominal) pain, wind and watery stools after drinking milk. The condition gets better when the infection is over and the intestinal lining heals. It is more common in children.

Haemolytic uraemic syndrome

Usually associated with traveller's diarrhoea caused by a certain type of E. coli infection, haemolytic uraemic syndrome is a serious condition where there is anaemia, a low platelet count in the blood and kidney damage. It is more common in children. If recognised and treated, most people recover well.

Guillain-Barré syndrome

This condition may rarely be triggered by campylobacter infection, one of the causes of traveller's diarrhoea. It affects the nerves throughout your body and limbs, causing weakness and sensory problems. See the separate leaflet called Guillain-Barré syndrome for more details.

Reduced effectiveness of some medicines

During an episode of traveller's diarrhoea, certain medicines that you may be taking for other conditions or reasons may not be as effective. This is because the diarrhoea and/or being sick (vomiting) mean that reduced amounts of the medicines are taken up (absorbed) into your body.

Examples of such medicines are those for epilepsy, diabetes and contraception. Speak with your doctor or practice nurse before you travel if you are unsure of what to do if you are taking other medicines and develop diarrhoea.

How long does traveller's diarrhoea last?

As mentioned above, symptoms are usually short-lived and the illness is usually mild with most people making a full recovery within in few days. However, a few people with traveller's diarrhoea develop persistent (chronic) diarrhoea that can last for one month or more. It is also possible to have a second 'bout' of traveller's diarrhoea during the same trip. Having it once does not seem to protect you against future infection.

How can I avoid traveller's diarrhoea?

• Avoid uncooked meat, shellfish or eggs. Avoid peeled fruit and vegetables (including salads).

• Be careful about what you drink. Don't drink tap water, even as ice cubes.

• Wash your hands regularly, especially before preparing food or eating.

• Be careful where you swim. Contaminated water can cause traveller's diarrhoea.

Regular hand washing

You should ensure that you always wash your hands and dry them thoroughly; teach children to wash and dry theirs:

• After going to the toilet (and after changing nappies or helping an older child to go to the toilet).

• Before preparing or touching food or drinks.

• Before eating.

Some antibacterial hand gel may be a good thing to take with you when you travel in case soap and hot water are not available.

Be careful about what you eat and drink

When travelling to areas with poor sanitation, you should avoid food or drinking water that may contain germs (microbes) or their poisons (toxins). Avoid:

• Tap water.

• Fruit juices sold by street vendors.

• Ice cream (unless it has been made from safe water).

• Ice cubes.

• Shellfish (for example, mussels, oysters, clams) and uncooked seafood.

• Eggs.

• Salads.

• Raw or undercooked meat.

• Fruit that has already been peeled or has a damaged skin.

• Food that contains raw or uncooked eggs, such as mayonnaise or sauces.

• Unpasteurised milk.

Drinking bottled water and fizzy drinks that are in sealed bottles or cans, tea, coffee and alcohol is thought to be safe. However, avoid ice cubes and non-bottled water in alcoholic drinks. Food should be cooked through thoroughly and be piping hot when served.

You should also be careful when eating food from markets, street vendors or buffets if you are uncertain about whether it has been kept hot or kept refrigerated. Fresh bread is usually safe, as is canned food or food in sealed packs.

Be careful where you swim

Swimming in contaminated water can also lead to traveller's diarrhoea. Try to avoid swallowing any water as you swim; teach children to do the same.

Obtain travel health advice before you travel

Always make sure that you visit your GP surgery or private travel clinic for health advice in plenty of time before your journey. Alternatively, the Fit for Travel website (see under Further Reading and References, below) provides travel health information for the public and gives specific information for different countries and high-risk destinations. This includes information about any vaccinations required, advice about food, water and personal hygiene precautions, etc.

There are no vaccines that prevent traveller's diarrhoea as a whole. However, there are some other vaccines that you may need for your travel, such as hepatitis A, typhoid, etc. You may also need to take malaria tablets depending on where you are travelling.

Antibiotics

Taking antibiotic medicines to prevent traveller's diarrhoea (antibiotic prophylaxis) is not generally recommended. This is because for most people, traveller's diarrhoea is mild and self-limiting. Also, antibiotics do not protect against nonbacterial causes of traveller's diarrhoea, such as viruses and parasites. Antibiotics may have side-effects and their unnecessary use may lead to problems with resistance to medicines.

Probiotics

Probiotics have some effect on traveller's diarrhoea and can shorten an attack by about one day. It is not known yet which type of probiotic or which dose, so there are no recommendations about using probiotics to prevent traveller's diarrhoea.