Free article: Managing an outbreak of norovirus

Published: Monday, 16 June 2014

Suzanne Averill explains how effective infection control can help prevent the spread of norovirus.

What is norovirus?

Norovirus, also known as the winter vomiting bug, is the most common cause of infectious diarrhoea and vomiting in the UK. Noroviruses are a group of viruses that cause gastroenteritis. They are highly infectious and spread easily among people. Norovirus can be caught in any environment, such as a hospital, care home or within the community, and can be responsible for large outbreaks of infection. Within health and social care environments this can have a huge impact on the provision of care for patients.

What are the symptoms of norovirus?

Symptoms of norovirus usually start with the sudden onset of vomiting, sometimes quite severe. Other common symptoms include diarrhoea and stomach cramps. Some people may also experience a raised temperature, headache and aching limbs. Not all of those who are infected will experience all of the symptoms.

The incubation period for norovirus is between 24 and 72 hours and people remain highly infectious for at least 48 hours after symptoms have settled. This can make transmission very difficult to control. Most symptoms last for 24 to 48 hours, although people may feel lethargic for a few days afterwards.

The illness itself is self-limiting, with symptoms lasting from 12 to 60 hours, with no long-term effects. Most people make a full recovery within two days; however some people may become dehydrated and require hospitalisation. These are usually more vulnerable people, such as the elderly.

Unfortunately, immunity is short-lived and therefore people may get re-infected with the virus.

How is it spread?

Norovirus is easily transmitted from one person to another. It is transmitted by contact with either contaminated food or water or by contact with a contaminated surface. Swallowing a very small dose of the infection may be enough to cause the illness. It is therefore essential to ensure good hand hygiene practices are carried out at all times in healthcare settings.

Who is at risk of getting norovirus?

Anyone is at risk of catching norovirus; however the very young and the elderly should take extra care if infected to ensure they don’t become dehydrated.

Is there any treatment?

There is no specific treatment for norovirus, but it is important to stop any laxatives a patient may be taking and make sure that fluid is replaced by drinking plenty of water to avoid dehydration.

If symptoms do persist for more than three to four days, or if an individual already has a serious illness, then their local GP should be contacted to provide medical attention.

How can norovirus be prevented?

Unfortunately it is not possible to prevent being infected by noroviruses, but some measures can be taken to reduce the risk. Paying attention to good hand hygiene measures is essential to reduce the risk of transmission. If you have been in contact with someone infected with norovirus it is important to wash your hands with soap and water.

Thorough cleaning of hard surfaces with a bleach-based solution, paying particular care to the toilet and surrounding area, will help to reduce contamination of the environment. Always take care when using bleach to avoid personal injury or damage to any furnishings.

How can a norovirus outbreak be managed?

Healthcare settings are a common place for outbreaks to occur as large numbers of people are together for several days, providing an ideal environment for the spread of the disease. If norovirus is brought into the healthcare setting by someone incubating the infection, then it can be easily spread amongst patients and staff.

Good infection control practices are important in preventing the transmission of infection. There are several measures you can take to reduce the risk of transmission.

Good hand hygiene
Washing hands with soap and water is key to preventing the spread of infection. Alcohol hand gel does not kill the norovirus and therefore should not be used during an outbreak. Staff should wash their hands before and after touching a patient. Hands should also be washed before handling any food, after using the toilet and after touching any contaminated surfaces.

Visitors should be encouraged not to visit during an outbreak as this increases the risk of spreading the infection further. If it is essential for the visitor to visit, they should not interact with patients other than the one they have come to visit. You should also ask them to follow the hand hygiene advice.

Isolating the patient
Patients with suspected or known norovirus should be isolated in a single room, preferably with their own toilet and sink. If this is not possible, there should be a designated area where patients who have symptoms are cared for. If there are large numbers of cases, an area, ward or care home may be closed to any further admissions or visitors to try and control the outbreak.

Cleaning is essential during an outbreak of norovirus to prevent new cases. Enhanced cleaning using a bleach-based solution is needed to eradicate the virus. All touch points, toilets and floors should be cleaned. Deep cleaning should be undertaken in the area surrounding a patient with norovirus, for example steam cleaning of soft furnishings. It is essential that vomit and diarrhoea are cleaned up immediately. Once an outbreak has been declared over, you must ensure that the area is deep cleaned again.

During an outbreak, good communication is essential. Staff need to be aware of who has symptoms so that they are able to monitor their condition and put good infection control practices in place.

Staff and visitors who develop symptoms must not enter the healthcare setting. They should remain away from the setting until they have been free from symptoms for at least 48 hours.

During an outbreak of norovirus, good documentation is vital for staff to have an understanding of the current situation. This allows staff to relay an accurate account of events to those outside the healthcare setting who are supporting the management of the outbreak, such as environmental health and the health protection agency.


Use the following items in the toolkit to put the ideas is this article into practice:

About the author

Suzanne Averill, MSc, RGN, Nurse Consultant, Global Infection Prevention, currently works for the United Nations in South Sudan as the Health and Nutrition Cluster Coordinator. She has previously worked for the Health Protection Agency as the International Lead and in commissioning in the NHS as Head of Infection Control.

This article was first published in the October 2012 issue of Quality & Compliance Magazine.

Most frequently read