Advice for patients, carers and visitors

What is viral gastroenteritis?

Viral gastroenteritis is an infection of the intestines causing diarrhoea and vomiting, which can lead to dehydration. This is a common infection which makes people feel unwell but, in most cases gets better with simple treatment.

Norovirus is the most common cause of infectious viral gastroenteritis (stomach bugs) in adults. Most cases of gastroenteritis in children are caused by a virus called rotavirus.

Norovirus and rotavirus infections can occur at any time during the year, but are renowned for causing infections during the winter months (and often called the winter vomiting bug).

Norovirus and rotavirus can be easily introduced into hospitals by infectious patients, staff and visitors.

How you can catch viral gastroenteritis

  • Being in contact with an infected person. Norovirus can be spread very easily from person to person
  • Consuming food or water contaminated with the virus
  • Contact with surfaces or objects that are contaminated with the virus and then putting your hand or fingers in your mouth
  • Swallowing the virus in the air after someone has had projectile vomiting (when the body expels vomit with more force than usual)
  • Consuming raw or undercooked food (particularly shellfish)

Outbreaks are most likely when people are in close proximity to each other, such as schools, nurseries, hospitals and similar settings.

What are the symptoms?

If you become infected with gastroenteritis or norovirus you will start to notice symptoms 12 to 48 hours later.

The main symptoms are:

  • Sudden onset of nausea (feeling sick) and /or vomiting, often projectile
  • Diarrhoea, which is often watery

You may also have:

  • Stomach pains
  • Headache
  • Not feeling well, discomfort and aching limbs
  • Fever

People with gastroenteritis may become dehydrated if they do not drink enough. This can make you feel tired, dizzy or lightheaded, have a dry mouth or tongue, or pass less urine than usual. Dehydration is more common in the elderly or frail and pregnant women.


Symptoms usually last for 1 to 3 days, but can sometimes last longer.

How to treat gastroenteritis

Most cases of gastroenteritis will improve over a few days. Treatment consists of ‘supportive measures’ such as:

  • When symptoms first develop, you may not want to eat. However, it is important that you continue to drink plenty of fluids (more than you would usually) to keep hydrated. If you feel sick, take small regular sips of water every few minutes
  • You may be prescribed an anti-emetic to reduce the sickness
  • Food can be gradually re-introduced when you feel able to tolerate it
  • Paracetamol may help if you have a headache or fever
  • You need to get plenty of rest

How to prevent spreading gastroenteritis

Gastroenteritis can spread very easily from person to person. You can’t always avoid getting gastroenteritis but good hygiene can prevent the virus from spreading.

Rigorous (thorough) cleaning is the most effective way of removing contamination from the environment. At the hospital we clean the wards and equipment to the highest standard.

You should always:

  • Wash your hands properly and regularly with soap and water, especially after using the toilet and before eating food. Soap and water is much more effective against these viruses than alcohol gel
  • If you are a patient and have diarrhoea or vomiting, please tell the nurses immediately
  • Tell relatives and friends not to visit if they have or have had any symptoms of diarrhoea and vomiting themselves in the previous 72 hours. Norovirus is serious and can spread more easily among people who are already ill
  • If you are visiting a patient who is suffering from gastroenteritis, wash your hands with soap and water before you leave their room

If you are in hospital with gastroenteritis

If you are admitted to hospital with viral gastroenteritis, you will be looked after in a single room until you have recovered and have not had any symptoms for 48 hours. The staff looking after you will wear gloves and aprons while caring for you.

If you become unwell after you have been admitted to hospital, you may be moved to a single room or a bay with other patients with the same illness.


We recommend that visitors are kept to a minimum while you have symptoms.

Visitors do not need to wear gloves and aprons unless they are providing you with personal care, they should wash their hands thoroughly with soap and water after visiting you


You will be discharged to your own home as soon as your team agree that you are well enough. This may be delayed until you have recovered if you have people coming into your home to look after you.


Any transfer to another hospital or nursing home may be delayed until you have recovered. Transfer may also be delayed if there is an outbreak of viral gastroenteritis on the ward.


If you are taking clothing from an infected person home to be washed, please follow the instructions below:

  • Wash clothing separately from other items
  • Nursing staff will place soiled items in a special plastic laundry bag called a Dissolvo sack. Dissolvo sacks can be placed directly into your washing machine without touching the contents in the bag. Full instructions are on the bag
  • Always wash hands thoroughly after handling soiled laundry

Outbreaks of gastroenteritis

Gastroenteritis spreads easily in healthcare settings and can be difficult to control. Viruses like norovirus and rotavirus are easily introduced by infected patients, staff or visitors. These viruses can survive in the environment for many days and can affect more than half of the people that are exposed to them.

Patients affected with the virus while they are in hospital are usually isolated for 48 to 72 hours after their symptoms have cleared.

To prevent any further transmission of the virus, if an outbreak is suspected the hospital may have to close affected wards to new admissions and discharges, restrict visiting and enforce strict hygiene measures.

Restricted visiting

Restrictions to visiting may be put in place if an outbreak of diarrhoea and vomiting is suspected. This means that we advise that you only visit if it is essential to the welfare of the patient or for compassionate reasons.


If you do visit, please be aware that you may be at risk of becoming ill yourself.

Any outbreak will be managed by the Infection Prevention and Control Team. The staff on the ward will try to keep you updated as much as possible during this time.

If it has been agreed that you can visit a ward that has been closed due to an outbreak, you must not go to any other ward or area within the hospital.

Always clean your hands thoroughly with soap and water after visiting.

If you develop any symptoms, do not visit until at least 48 hours after the symptoms have stopped.

Visitors that are not in good health themselves are discouraged from visiting. Children and the elderly are at greater risk of catching gastroenteritis and being more unwell.

Contact information

If you have any questions regarding an outbreak, please ask to speak to the nurse in charge on the ward or if any further information needed contact the Infection Prevention and Control Nurses.

Gloucestershire Hospitals Infection Prevention and Control Team

Tel: 0300 422 6122

Monday to Friday, 9:00 to 4:00


If you have any concerns, please contact the Patient Advice and Liaison Service (PALS).


Tel: 0800 019 3282


Further information

NHS UK - Diarrhoea and Vomiting


Printable version of this page

Viral gastroenteritis GHPI0550_11_22 Department: Infection control Review due: September 2024 PDF, 199.3 KB, 6 pages
Reference number GHPI0550_11_22
Department Infection control
Review due September 2024