Infection, Prevention & Control - Norovirus - Your questions answered

What is Norovirus?

Norovirus causes diarrhoea and vomiting is one of the most common stomach bugs in the UK. It's also called the ‘winter vomiting bug’ because it’s more common in winter, but you can catch it at any time of the year. It can be very unpleasant, but usually clears up by itself in a few days.

Norovirus can spread easily through communities and so outbreaks are common in settings where individuals have close contact such as hospitals, care homes, schools, and nurseries.

The incidence of norovirus in the UK has been estimated at 3 million cases annually with approximately 3000 people admitted to hospital. The impact of norovirus is associated with significant disruption and costs to healthcare systems.

What are the symptoms?

Norovirus symptoms include:

• Nausea
• Vomiting and/or diarrhoea with abdominal cramps
• Fever
• Headaches and muscle aches

Symptoms often begin suddenly within 12-48 hours of being infected. You will usually start to feel better in 48-72 hours.

How serious is norovirus?

Although unpleasant, the symptoms are usually quite mild and self - limiting with no long-term health effects. However, some people may become dehydrated due to the amount of fluid they have lost and may require some fluid replacement.

Severe dehydration is usually only seen in the very young, the elderly, or those with immune systems which are not functioning well. Even in these individuals, a full recovery is normal.

Dehydration can be prevented by drinking plenty of fluids.

If your symptoms haven’t improved after three days of sickness, or if you experience sudden worsening of symptoms or pain, or suspect you, or someone you are caring for is severely dehydrated and you need some advice, ring the NHS non-emergency
number 111. In medical emergencies always dial 999.

How does it spread?

Norovirus is a highly infectious virus and spreads very easily in public places such as hospitals, nursing homes and schools.

Noroviruses are relatively resistant in the environment: they can survive freezing as well as high temperatures (up to 60°C). The viruses survive long periods on different surfaces.

The virus cannot be seen with the naked eye and people can become infected in the following ways:

• Close contact with someone with norovirus, who may breathe out small particles of the virus that you then inhale
• Touching surfaces or objects that have the virus on them, then touching your mouth
• Eating food that's been prepared or handled by someone with norovirus

Who gets norovirus?

Norovirus can affect anyone and at any age. You can get norovirus more than once because the virus is always changing, and your body is unable to build up long-term resistance to it.

What is the treatment for norovirus?

There is no treatment for norovirus apart from letting it run its course and to drink plenty of fluids to avoid dehydration.
Antibiotics won’t help because norovirus is caused by a virus.

How can the spread of norovirus be prevented?

It’s not always possible to avoid getting norovirus, but following this advice can help stop the virus spreading:

• All patients, staff and visitors are encouraged to wash their hands thoroughly with soap and water
• Be aware alcohol-based hand gels do not kill the virus
• In hospital, infected patients may be nursed in single side rooms or nursed together in bays with the doors closed. This is to help prevent the spread of the virus to unaffected areas and other susceptible patients
• During outbreaks, visiting restrictions may be put in place to reduce the risk of spread to relatives and friends
• Visitors will not be expected to wear gloves and aprons unless assisting a patient with personal care
• Food, such as fruit, sweets and biscuits should not be left open and exposed as it could potentially become contaminated and spread infection if consumed. Fruit should be washed/peeled before eating

How to stop spread of norovirus at home?

• Wash your hands frequently and thoroughly with soap and water particularly after using the toilet and before preparing or handling food
• Disinfecting any surfaces or objects that could be contaminated, using a bleach-based household cleaner
• Washing any items of clothing or bedding that could have become contaminated separately on a hot wash (60°C) to ensure the virus is killed
• Not sharing towels and flannels
• Flushing any faeces or vomit in the toilet and cleaning the surrounding area with a bleach-based household cleaner
• Stay off work or school until at least 48 hours after the norovirus symptoms have stopped
• Avoid visiting anyone in hospital during this time

Further reading

www.nhsinform.scot/illnesses-and-conditions/infections-and- poisoning/norovirus/

www.nhs.uk/conditions/norovirus/

Guidelines for the management of norovirus outbreaks in acute and community health and social care settings (publishing.service.gov.uk)

Norovirus: What to do if you catch it and helping to stop the spread – UK Health Security Agency (blog.gov.uk)

www.journalofhospitalinfection.com/article/S0195