Digestive health centre

Understanding the norovirus or 'winter vomiting bug'

What is the norovirus?

Noroviruses are the most common cause of upset stomach.

They’re sometimes called “small round structured viruses” (SRSV) or “Norwalk-like viruses”. However, most people are familiar with them as “the winter vomiting bug” because they’re most likely to catch them during the winter months.

Noroviruses can occur at any time of the year, and the NHS estimates that between 600,000 and one million people get them in the UK in any one year.

You may become aware of outbreaks of the norovirus in news reports of large groups of people becoming ill, for instance in hospitals, schools or on cruise ships. Outbreaks of norovirus in hospitals usually lead to ward closures and visiting time restrictions.

What are the symptoms of norovirus?

Norovirus causes upset stomach ( gastroenteritis), and the main symptoms are diarrhoea and vomiting. Some people also experience fever, headache, stomach cramps or aching limbs.

Although it’s an unpleasant illness, it is generally mild and people usually recover within two to three days of being infected.

How can it be treated?

Norovirus can’t be “cured” and there are no specific medicines that can be taken if you catch the “winter vomiting bug”. The usual advice is to let the illness “run its course”.

Make sure you drink plenty of water to replace the fluids lost in your body through diarrhoea and vomiting. This is particularly important for young children and the elderly.

If you feel like eating, choose foods that can be easily digested.

How can I help prevent catching norovirus?

Good hygiene is the key to lowering the risk of being infected by norovirus and preventing its spread to others.

Advice from the NHS and the Health Protection Agency is to

• Wash your hands with soap and water, particularly before preparing food and after using the toilet
• Clean surfaces with a bleach solution, paying particular attention to the toilet and toilet area
• Clean up any vomit as well as the surrounding area
• Flush away any faeces in the toilet
• Wash any clothing or bedding that may have been contaminated

If you have developed norovirus, you should avoid contact with others for at least 48 hours after your symptoms have gone.