IF you fall sick with norovirus, it could be because you've inhaled someone else's vomit.

Experts are warning that the debilitating bug can become airborne and therefore way more contagious than many of us think.

Dr Daniel Quemby says that norovirus is more common during the winter, and if throws up near you, there's a good chance you could catch it too.

"Norovirus is the most common cause of viral gastroenteritis and (can be) spread through swallowing the virus in the air after someone has vomited, as the virus can become airborne for a while in this instance", he said.

Norovirus (AKA the "winter vomiting bug") is an unpleasant stomach virus that causes vomiting and diarrhoea which comes on quickly, lasting for up to 48 hours.

Here are five other facts you may not have known about the virus, to help you feel prepared in case you encounter it this winter:

1. You're contagious for at least two days
Even after the symptoms have subsided, you could still be contagious for another 48 hours.

Dr Quemby says: "Avoid visiting any hospitals, care homes or GP surgeries if you have had the typical symptoms of viral gastroenteritis in the past 72 hours because Norovirus can easily spread among people who are already ill and is more serious.”

2. You can't become immune to norovirus
Just because you've had the virus once, doesn't mean that you won't catch it again.

“It’s actually difficult to estimate how it will spread as the genetic code of the norovirus is able to recombine and mutate.

"New variants can emerge to become the dominant strains in a certain period, which our immune systems do not recognise, therefore norovirus infections are difficult to prevent and control.”

3. It's way more common in winter
“Norovirus is the leading cause of acute gastroenteritis outbreaks worldwide with around 600,000 to 1 million people getting norovirus every year," Dr Quemby explains.

"It is more common in the winter months but can actually occur at any time of year.”

4. It spreads quickly through offices and schools
It's more likely to spread in places like hospitals, schools and nursing homes
Outbreaks tend to happen in spaces where people spend a lot of time together in enclosed spaces - like schools, hospitals and cruise ships.

"These outbreaks tend to occur more in the winter months when we are shut indoors with the heating on, poor ventilation and our immune systems may be reduced."

5. You can get it from eating raw or undercooked food
As well as inhaling other people's vomit, you can get the virus from touching contaminated surfaces, drinking contaminated water and consuming raw or undercooked food.

Shellfish is particularly risk, Dr Quemby says, because ti can be contaminated with raw sewage. Gross.

Will there be an outbreak this year?
Over the summer, there were reports of a Norovirus outbreak, with many Brits suffering from the symptoms.

The outbreak emerged in the West Midlands, Greater Manchester, Suffolk, Lincolnshire, Devon, Cornwall, North Wales and South Wales.

Parents claimed students at Westclyst and Broadclyst Primary Schools in Exeter were forced to carry sick buckets, with one parent saying it was like "something from a horror film".

Public Health England has now been called upon to help manage the outbreak.

Speaking to the Sun Online, Broadclyst Community Primary School headteacher Jonathan Bishop said: "We are having extra deep cleans during the day and at the end of the day, which includes things like cleaning door handles.

"The school nurse is also going into classes telling children about the importance of handwashing."

The bug is set to get worse over the winter.

It was announced earlier this month that the bug may sweep schools and offices this winter.

In early January 2018, it was confirmed that hospitals across the North East had imposed visitor restrictions as a result of a Norovirus outbreak.

They were first imposed around a week before Christmas.

During the second week of January, it was announced that cases had risen by a third in just a week.

Across England, 944 hospital beds were closed due to the winter vomiting bug, up 29 per cent from 731 the week before.

Although there is no treatment for norovirus, you can improve symptoms by resting and drinking plenty of water to avoid becoming dehydrated.

Norovirus is one of the most common stomach bugs in the UK and is also referred to as “the winter vomiting bug”, although it can affect people all year round.

Around 3 million people get it every year in the UK - 300 of which die from the virus.

Dr Quemby advises: “If you’ve been suffering from diarrhoea, water alone is not always enough.

"While it can help you to rehydrate, it does not replace the essential salts lost through diarrhoea.

"Take an oral rehydration therapy to replace lost salts to help your body rehydrate and recover faster."