Norovirus (Viral gastroenteritis)

Noroviruses are a group of viruses that are the most common cause of diarrhoea and/or vomiting in England and Wales. In the past, noroviruses have also been called ‘winter vomiting viruses’, ‘small round-structured viruses’ or ‘Norwalk-like viruses’.

The virus is easily transmitted from one person to another. It can spread via contact with an infected person or contaminated surfaces or objects, or by consuming contaminated food or water.

Diarrhoea and/or vomiting will begin around 12-48 hours after becoming infected. The illness is self-limiting and the symptoms will last from approximately 12-60 hours. They will start with the sudden onset of nausea often followed by projectile vomiting and/or watery diarrhoea.

Some people may have a raised temperature, headache and aching limbs. Most people make a full recovery within 1-2 days, however some people (usually the very young or elderly) may become dehydrated, be ill for longer and may require hospital treatment.

Norovirus often causes outbreaks because it is so easily spread from one person to another. Because there are many different strains of the virus and immunity is short-lived, outbreaks tend to affect more than 50% of susceptible people.

Outbreaks usually affect people who are in a semi-closed environment such as hospitals, nursing homes, schools and on cruise ships. Anywhere that large numbers of people congregate for long periods of time provides an ideal environment for the infection to spread.

Outbreaks can be difficult to control because the virus is so easily spread. The most effective way to limit any spread is to have good measures of hand and environmental hygiene and to isolate groups of those affected (cohorting) for up to 48 hours after their symptoms have stopped. In hospital this includes restricting the number of visitors, staff and relatives to the affected ward.

There is no specific treatment. The illness runs its course. It is important to drink plenty of fluids to prevent dehydration. In severe cases hospitalisation may be necessary.

Good hygiene is of the utmost importance, particularly thorough hand washing. You should avoid preparing food for others until 72 hours after the symptoms have stopped.

Do not visit friends or relatives until at least 48 hours after symptoms have stopped, this includes hospital visits.

It is impossible to totally prevent infection, however taking good hygiene measures such as frequent hand washing when around someone who is infected is important. Good environmental hygiene is important, as is the prompt cleaning and disinfection of contaminated areas.

Isolating groups (cohorting) of affected people until 48 hours after symptoms have stopped is also important in limiting the spread of the infection in a hospital environment. If you are unwell, or have been in contact with someone who is infected, you should not visit anyone in hospital until at least 48 hours after symptoms have stopped.

Please speak to any of the ward staff who are caring for you. If they are unable to answer your questions, or if you require further information, the Infection Control nurses will visit you on the ward, or are available via the hospital switchboard.

Their direct telephone number is 01473 703485 or 01473 703742 and they are available Monday – Friday, 9 am – 5 pm.

If there are cases of norovirus on a ward please do not visit unless it is essential and do not visit with young children or babies.

Please wash your hands before and after visiting.