Gastroenteritis is an infection of the stomach and bowel. The most common symptoms are repeated episodes of diarrhoea (three or more episodes over the space of 24 hours) and vomiting.

How common is gastroenteritis?

Gastroenteritis can be caused by a virus, such as the norovirus, or by a number of different bacteria. Typically, bacterial gastroenteritis develops as a result of food poisoning.

How gastroenteritis is spread

Most forms of gastroenteritis are highly infectious. The condition is mainly spread through what is known as the faecal/oral route - when bacteria found in faeces (stools) are transferred to your mouth.

Bacteria can be transferred this way through poor hygiene. For example, if someone does not wash their hands after going to the toilet, any viruses or bacteria on their hands will be transferred to whatever they touch, such as a glass, kitchen utensil or food. If you touch this contaminated object and then touch your face, or if you eat contaminated food, you may swallow some of the viruses or bacteria. This will then cause the symptoms of gastroenteritis.

If you or your children have gastroenteritis, you should not return to work or let your children return to school or nursery until 48 hours after passing a normal (solid) stool.


Most people with gastroenteritis will experience only mild symptoms and the condition will get better within a few days without the need for treatment.

However, if symptoms are severe, or if the person is vulnerable because of their age or because of another illness, hospital treatment may be required. This is because diarrhoea can cause a person to become quickly dehydrated, which in severe cases can be fatal.



The sac-like organ of the digestive system. It helps digest food by churning it and mixing it with acids to break it down into smaller pieces.
Diarrhoea is the passing of frequent watery stools when you go to the toilet.
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and some others are good for you.
Antibiotics are medicines that can be used to treat infections caused by micro-organisms, usually bacteria or fungi. For example amoxicillin, streptomycin and erythromycin.
Last updated: 04 October 2011

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