Bowel infections

Bowel infections happen when microorganisms (‘bugs’ or germs) get into your gut. The gut (also called your bowel or intestine) is part of your digestive system.

An infection of the bowel is sometimes called a gastrointestinal infection, or gastroenteritis (gastro).

You can get gastroenteritis by eating or drinking contaminated water or food. This is often called food poisoning.

You can also get gastroenteritis from contact with germs spread from infected people or contaminated objects such as

• cutlery
• taps
• toys
• nappies

Bowel infections are common in Australia, but you can also get them when travelling overseas.

Infections of the bowel can happen to anyone at any time. They can cause a lot of discomfort and inconvenience. They can sometimes lead to more serious problems.

Some common symptoms of bowel infection include:

• diarrhoea
• nausea
• vomiting
• crampy abdominal pain
• fever
• headache

Some people also get blood in their stools (poo), including if they have an infection known as dysentery.

Blood in stools can be caused by bacteria or parasites. It may be something more serious, so you should always see a doctor if you have blood in your stools.

Bowel infections are most often caused by viruses, such as:

• rotavirus: common in young children — spreads easily through contact with contaminated vomit or faeces (poo) and can cause severe illness in young children.
• norovirus: highly contagious and spreads easily in places like childcare centres, nursing homes and cruise ships.

Bacteria that can cause bowel infections include the following:

• campylobacter: often linked with eating contaminated chicken. People most at risk are young children (under 5 years old), older people, people with a weakened immune system and people who are travelling.
• salmonella: usually spread via contaminated meat, poultry or eggs.
• shigella: most common in people who have travelled to developing countries.
• clostridium difficile: usually linked to recently taking antibiotics or being in hospital.

Parasites that can cause bowel infections include the following:

• giardia: spread in the faeces of infected people and animals. It’s most common in young children, hikers and travellers.
• cryptosporidiosis: spread by contaminated food or water.
• amoebiasis: mostly affects young adults, and is usually spread through contaminated water or food.

If you often get bowel symptoms such as diarrhoea, it could be a sign that you have an underlying condition such as:

• diverticular disease
• irritable bowel syndrome
• Crohn's disease
• ulcerative colitis

You should see your doctor for advice.

Make an appointment to see a doctor if you or your child have:

• a high temperature (fever)
• severe abdominal (tummy) pain
• blood or mucus in your stools
• diarrhoea that lasts longer than 2 or 3 days
• signs of dehydration, such as excessive thirst or not passing much urine (wee)

If your baby is younger than 6 months old and has diarrhoea, see a doctor right away.

When to seek urgent care 

To diagnose the cause of your symptoms, your doctor may ask some questions and examine you. Usually, tests are not needed to diagnose gastroenteritis.

However, in some situations, your doctor might recommend tests, such as:

• faecal testing (taking a stool sample)
• blood tests
• an endoscopy (such as colonoscopy) to look inside your bowel

In some cases, you might be referred to an infectious diseases service.

Most bowel infections go away after a few days.

It’s important that you drink plenty of fluids, including water and oral rehydration drinks. This is to avoid dehydration. Oral rehydration drinks are available from pharmacies and some supermarkets. Some brands are also available as icy poles.

You may need to take antibiotics for bowel infections caused by parasites and bacteria.

Babies and older people

Diarrhoea causes a lot of fluid to be lost from the body. Take special care of vulnerable people like very young children, older people and those in poor health.

Children who refuse water and oral rehydration drinks can be given diluted apple juice in the short-term.

Babies who are breastfeeding need to be breastfed more often to keep up their fluid intake. You can also include some oral rehydration solution for the first 12 hours.

Formula-fed babies should be given oral rehydration solution or water for the first 12 hours. After that, give them normal formula in smaller, more frequent amounts.

If your symptoms persist (don’t get better), see a doctor.

Bowel infections can sometimes cause complications, such as:

• electrolyte (salt) imbalance — caused by losing too much water
• kidney failure — this is rare
• food intolerances — this can happen rarely, when a bowel infection causes problems with your digestion

Many bowel infections can be prevented by taking care with what you eat and drink and by following good hygiene practices. You should:

• always cook foods such as meat and eggs thoroughly
• wash your hands regularly, especially before touching food and after nappy changes
• avoid close contact with people who have a bowel infection

When travelling to areas where clean water and food hygiene cannot be guaranteed, you should:

• only use bottled water for drinking and teeth cleaning
• avoid drinks with ice
• choose freshly cooked foods that are served steaming hot
• avoid raw or under-cooked foods (especially meat or seafood)
• avoid fresh salads, peeled fruit and unpasteurised milk or milk products
• avoid food from roadside stalls

If you or your child has a bowel infection, stay home from work or school until the vomiting and diarrhoea has stopped for at least 48 hours. This will stop other people from getting sick.

In Australia, vaccination against rotavirus is recommended for all babies under 6 months of age. It’s a routine vaccine given as part of the National Immunisation Program. Vaccinating your baby can reduce their risk of becoming very unwell with a bowel infection. This vaccine is given orally (by mouth).

The Royal Children's Hospital has more information about the symptoms and management of gastroenteritis in children (Opens in new tab).

The Sydney Children’s Hospital Network has information about how to treat your child at home (Opens in new tab). 

Languages other than English

Health Translations has several translated factsheets on conditions related to diarrhoea.

• Rotavirus
• Gastroenteritis in children
• Giardiasis

The Royal Children's Hospital has Kids Health Information on gastroenteritis available in multiple languages.