The following information is to be used as a guide and at the discretion of the end-user and should not replace a doctor’s opinion.
OVERVIEW
Norovirus is the world’s most common stomach bug, responsible for more than 685 million cases globally each year. It is highly contagious and spreads rapidly in households, schools, restaurants, and cruise ships. While it is usually short-lived and self-limiting in healthy adults, it can be dangerous for young children, the elderly, and the immunocompromised.
There is no vaccine and no specific treatment, but practical hygiene measures are highly effective.
WHAT IS NOROVIRUS?
Norovirus is a gastrointestinal virus that attacks the lining of the stomach and intestines, causing the sudden, unpleasant symptoms that most of us have experienced at some point in our lives. Often referred to as a “stomach bug” or a “bad stomach,” the norovirus is actually a specific virus, and not related to influenza.
It is a remarkably resilient virus and the World Health Organisation (WHO), states that norovirus is the leading cause of acute gastroenteritis (inflammation of the stomach and intestines) in people of all ages, worldwide:
- 685 million: the estimated number of norovirus cases globally each year
- 200 million: the number of cases in children under five
- 200 000: global norovirus-related deaths per year, usually in low-income countries
HOW DOES NOROVIRUS SPREAD?
Unlike hantavirus, which primarily spreads through contact with rodents, norovirus is directly and readily transmissible from person to person. The CDC identifies three main routes of spread:
- Direct contact with an infected person: caring for someone who is ill or sharing food and utensils with them.
- Contaminated food or water: particularly shellfish (like oysters), raw fruits and vegetables, and any food prepared by an infected person who has not washed their hands.
- Contaminated surfaces: touching a surface where the virus has landed (e.g. a doorknob, lift button, or shared bathroom) and then touching your mouth.
A particularly important and often overlooked route is aerosolised vomit. When an infected person vomits, microscopic viral particles become airborne and can settle on nearby surfaces or be inhaled by people in the same room. This is one reason norovirus can sweep through households, schools, and ships so rapidly.
It is also important to note that you can still transmit norovirus to others for up to 48 hours after your symptoms have disappeared. This is why staying home and maintaining rigorous hand hygiene even after you feel better is so important, especially before preparing food for others.
WHAT ARE THE SYMPTOMS OF NOROVIRUS?
Norovirus typically strikes fast: symptoms usually begin 12 to 48 hours after exposure. The illness is unpleasant but usually brief; most healthy adults recover within 1 to 3 days.
NOROVIRUS IN SOUTH AFRICA
Norovirus is present in South Africa and has been documented here since 1993. Every year, there are localised outbreaks which typically manifest as rapid surges in nausea, watery diarrhea, and vomiting in communal settings like schools, restaurants, cruise ships, and households. Although outbreaks occur year-round, they tend to peak during cooler months from May to August, often circulating alongside other intestinal viruses like rotavirus and adenovirus..
For the vast majority of healthy adults, norovirus is a deeply unpleasant but short illness that resolves on its own within a few days. However, it should be taken seriously, particularly if you have young children, elderly relatives, or anyone in your care with a compromised immune system. The WHO notes that norovirus causes an estimated 50 000 child deaths per year globally, almost all in low-income settings where access to rehydration is limited. In South Africa’s lower-income communities, where diarrhoeal disease is already a burden, norovirus is particularly dangerous.
HOW TO PROTECT YOURSELF AND YOUR FAMILY
Because there is no vaccine and no specific treatment, prevention is everything. The good news is that the measures that work are practical and within everyone’s reach:
MAKE YOUR OWN REHYDRATION SOLUTION
- Make sure your hands and all the utensils you are using are washed in soap and clean water.
- Boil one litre of water and allow it to cool.
- Add 8 (eight) level teaspoons of sugar and a half a level teaspoon of salt to the cooled water.
- Stir well until all the sugar and salt is dissolved.
Drink the solution after each watery stool. Adults should drink as much of the solution as they can, while children should be dosed as follows:
- Under 2 years old: 1/4 to 1/2 of a large (250 ml) cup of the solution after each watery stool. Offer one teaspoon every one to two minutes.
- Two years and older: at least 1/2 to 1 large (250 ml) cup of the solution after each watery stool. Encourage the child to take frequent sips.
If vomiting accompanies the diarrhoea, don’t stop offering or drinking the solution. Pause for 5 – 10 minutes and then restart at a slower pace. Infants who breastfeed should continue for as long as they will feed.
FURTHER READING
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