What is a Norovirus?

Noroviruses are a group of related viruses that cause gastroenteritis. Norovirus infections are extremely contagious and spread quickly through closed communities such as hospital wards, schools, nurseries and cruise ships.

The norovirus infection is often referred to as the “winter vomiting bug” though it is possible to catch it at any time of the year.

Symptoms of norovirus

The symptoms of norovirus are distinctive, and include:

  • sudden nausea
  • projectile vomiting
  • watery diarrhoea
  • painful stomach cramps
  • some people also report aching limbs, a slight fever and/or headaches.

Symptoms appear 1 to 2 days after becoming infected and usually last no more than 3 days.


There are no simple treatments for norovirus; antibiotics do not work as the infection is caused by a virus. It is best to let the body clear the virus in due course whilst remaining at home. Medical advice is not usually required, and visiting environments filled with people such as the GP surgery will put others at risk; if concerned it is best to call for advice.

To help improve symptoms:

  • Drink plenty of fluids to avoid dehydration. The body will lose quite a lot of fluids through vomiting and diarrhoea; babies and elderly people are particularly at risk
  • Take paracetamol for any fever or aches and pains
  • Get plenty of rest
  • If eating try to stick to plain foods such as soup, bread or rice.
  • Rehydration drinks made from sachets bought from pharmacies will help if you have signs of dehydration, such as dark urine, dizziness or a dry mouth.


Norovirus can spread very easily, and maintaining high standards of hygiene is vital to avoiding the bug. Hands should be washed regularly whilst you are ill and it is necessary to stay off work or school until at least 48 hours after the symptoms have cleared, to reduce the risk of passing it on.

Disinfect any surfaces or objects that may have been contaminated, preferably using a bleach-based household cleaner. Wash any items of clothing or bedding that could have become contaminated separately on a hot wash to ensure the virus is killed, and sure no towels or flannels are shared.

Avoid eating raw, unwashed food produce; be extremely wary of eating oysters as they can carry norovirus.

Maintaining a strong immune system by having the recommended daily allowance of fruit and vegetables, cutting back on alcohol and avoiding cigarettes will also help to prevent infection.

When to seek Further Advice

If there is a risk of a more serious problem, it will be necessary to contact the G.P for further advice. Seek medical advice if:

  • your baby or child has passed six or more watery stools in the past 24 hours, or has vomited more than three times
  • your child is less responsive, or has developed a fever
  • you notice symptoms of severe dehydration; remember babies and elderly people are at greater risk of becoming dehydrated
  • you have bloody diarrhoea
  • symptoms have not started to improve after a few days
    you or your child have a serious underlying condition, such as kidney disease, and have diarrhoea and vomiting

Your GP may suggest sending off a sample of your stool to a laboratory to confirm the presence of norovirus or establish if you have another infection.