Norovirus

The norovirus group of viruses are the most common cause of gastroenteritis (upset stomach) in the UK. They are also known as small round structured viruses (SRSV) or Norwalk-like viruses.

Norovirus infections are sometimes called winter vomiting disease because people often get them during the winter months. However, they can occur at any time of the year.

Symptoms of a norovirus infection include nausea, vomiting, diarrhoea and in some cases a fever, headache, stomach cramps and aching limbs. Symptoms can last for 12 to 60 hours, but most people recover within two days (see Symptoms for more information).

How noroviruses are spread

It is estimated that noroviruses infect between 600,000 and one million people in the UK every year. Norovirus infections occur in people of all ages and outbreaks of the illness are common, particularly within contained environments such as hospitals, nursing homes and schools. This is because the norovirus spreads very easily from person to person and can survive for several days in a contaminated area.

Noroviruses can be spread through contact with an infected person, through contact with surfaces or objects that are contaminated with the virus, or by consuming contaminated food or water.

After having a norovirus infection it is possible to become infected again, because immunity to the virus only lasts for a short period of time.

Outlook

There is no specific treatment for a norovirus infection and usually you will not need to see a doctor as the symptoms leave after a couple of days.

Treatment

You should:

• stay at home
• take paracetamol to relieve symptoms of any fever
• drink plenty of water to replace the fluids lost through diarrhoea and vomiting. This prevents dehydration which  is particularly important for young children and the elderly, who are more prone to dehydration
• try to eat a light diet of foods that are easy to digest, such as soup, rice, pasta and bread. Babies should be given their normal feed throughout
• reduce the risk of passing the virus onto others by washing your hands regularly and staying at home until you are clear of symptoms for 48 hours.

If your symptoms continue for more than three days or you feel severely dehydrated, seek medical attention immediately.