Food Safety
July 11, 2022

Norovirus: Facts You Need To Know

Recently, I have had to consult businesses reeling from Norovirus outbreaks, both in the Maldives and abroad, and this compelled me to study this virus a bit more.  As a result, I came across some stunning medical stories that caused me to clean my glasses and take another look to make sure I’m reading it clearly.

Did you know that norovirus is the most common cause of acute gastroenteritis in the world, causing an estimated 685 million cases every year globally. About 200 million cases are seen among children under 5 years old, leading to an estimated 50,000 child deaths every year, mostly in developing countries.

What is this fearsome bug, you may be asking, and why isn’t it the subject of a Hollywood horror movie? Noroviruses are one of virology’s great open secrets. The bug has been unceremoniously crowned as, “perhaps the perfect human pathogen.”

And why is that?

Each norovirus carries just nine protein-coding genes (you have about 20,000). Even with that skimpy genetic toolkit, noroviruses can break the locks on our cells, slip in, and hack our own DNA to make new noroviruses. They clearly know how to exploit their hosts. And once vast numbers have been made, they come roaring out of the body. Within a day of infection, noroviruses have rewired our digestive system so that stuff comes flying out from both ends.

Noroviruses make us puke. Vomiting occurs when our nerves send signals that swiftly contract the muscles lining the stomach. Vomiting does us a lot of good when we’re hurling out some noxious substance that would do us harm. But repeated projectile vomiting of the sort that noroviruses cause serve another function: they let the viruses to find anew host.

In the other end, to trigger diarrhoea, the viruses alter the intestinal lining, causing cells to dump out their fluids, which then gets washed out of the body–along with many, many, many noroviruses. Each gram of faeces contains around five billion noroviruses. (Yes, 5 billion.)

Once the norovirus emerges from its miserable host, it has to survive in the environment. Noroviruses have no trouble doing so, it seems. Fine droplets released from sick people can float through the air, even distances, and settle on food, on countertops, in swimming pools. They can survive freezing and heating and cleaning with many ordinary chemicals. In 2016, scientists surveyed a hospital for noroviruses and found 21different types sitting on a single countertop. It takes fewer than twenty noroviruses slipping into a person’s mouth to start a new infection.

Noroviruses are so good at spreading that it’s quite likely that at some point in your life, you’ve had a norovirus infection. (You may have wrongly called it a flu, or stomach bug)

So–here’s what you can do to get rid of noroviruses



Disinfectants at the correct concentration should be applied too hard, nonporous, environmental surfaces. Bathrooms, door knobs, and other places where the virus is likely to be lurking when someone’s sick in the premises should be on the to-clean list.


Overall, studies suggest that proper hand-washing with soap and running water for at least 20 seconds is the most effective way to reduce norovirus contamination on the hands. Forget all the fancy alcohol and antibiotic-laced potions. Antibacterial products affect only bacteria, they are less affective against flu bugs, which are viruses.

Correct clean up of vomit and diarrhoea

After a sick person vomits or has diarrhoea, custodians need to immediately clean and disinfect the contaminated surfaces. Staff should wear personal protective equipment, including disposable gloves, aprons and masks.

Prompt removal of infected people from public areas

If someone has vomited, it is imperative that they are removed from public areas, safely, and as quickly as possible.

And last but not least….

Don’t be Mister Tough Guy; stay at home! 

Considering the highly infectious nature of norovirus, exclusion and isolation of infected persons are often the most practical means of interrupting transmission of virus and limiting contamination of the environment.

Written by
Babli Jahau