Norovirus: signs and symptoms, how is it spread, what is the incubation period and how long does it last?

• Norovirus cases have continued to surge across the UK.
• The new ‘Kawasaki’ norovirus strain now accounts for nearly 70% of all cases.
• Norovirus is highly contagious and cannot be killed by alcohol hand gels.

Norovirus cases are still surging in the UK, with high numbers of cases being driven by the new ‘Kawasaki’ strain.

Latest figures from the UK Health and Security Agency (UKHSA), show that between weeks 44 and 45 of 2024 the number of norovirus cases was 85% higher than the five season average for the same two week period, with the ‘Kawasaki’ strain accounting for 67% of cases.

Often described as the “winter vomiting bug” even though you can get it at any time of the year, norovirus is highly contagious and causes symptoms including nausea, vomiting and diarrhoea.

This is everything you need to know about how norovirus is spread and what symptoms you need to watch out for.

How is norovirus spread?

Norovirus is highly contagious and can easily spread between people. It can be caught from close contact with someone who has norovirus, touching surfaces or objects that have the virus on them and then touching your mouth or by eating food that has been prepared or handled by someone with norovirus.

Alcohol hand gels do not kill norovirus so the best way to prevent catching it and to stop it spreading is to wash your hands regularly with soap and water.

What is the incubation period?

Norovirus has a fast incubation period between catching the virus to developing symptoms of 12 to 48 hours.

What are the symptoms of norovirus?

Symptoms of norovirus usually start suddenly, within one to two days of being exposed to the virus.

The symptoms of norovirus can include:

• feeling sick (nausea)
• diarrhoea
• being sick (vomiting)
• a high temperature
• a headache
• aching arms and legs

You will usually start to feel better within two to three days with symptoms often best managed at home. The most important thing for recovery is to rest and drink plenty of fluids to avoid dehydration.

It’s also advised that you stay off school or work until you have not had symptoms for at least two days and do not visit hospitals or care homes during this time as you are still infectious.

If you are worried about yourself or someone that you care for contact your GP or local NHS service for more information. If you or someone that you care for vomits blood, has vomit that looks like ground coffee, is a child with yellow-green vomit, may have swallowed something poisonous, have a stiff neck and pain when looking at bright lights or have a sudden, severe headache or stomach ache contact 999 or attend your nearest accident and emergency service.

What is the new norovirus strain?

The ‘Kawasaki’ norovirus strain, which was first identified in Kawasaki, Japan in 2014, has quickly became a dominant variant in the UK, accounting for 67% of recent cases. Despite being a different strain, the symptoms of ‘Kawasaki’ norovirus remain the same as other norovirus infections.

You can find out more about the signs and symptoms of norovirus at NHS.UK.