Overview

Norovirus is commonly referred to as the "winter vomiting bug" in the UK due to its prevalence during winter months. However, it can actually infect individuals year-round. It is the leading cause of viral gastroenteritis, resulting in symptoms like vomiting and diarrhoea. There is no specific treatment for norovirus, so it is important to stay home until you recover. 

While healthcare professionals may recommend over-the-counter medications for symptom relief, caution is advised. Hospitals, assisted living facilities, daycare centres, and schools are among the closed, congested settings where norovirus infections frequently occur. Recognising severe symptoms that require urgent medical attention is especially crucial for high-risk individuals. The primary focus of treatment is to prevent dehydration by restoring lost fluids and ensuring adequate rest. It is very important to avoid contact with others while infectious and to practise good hygiene to protect yourself and those around you from spreading the virus.¹

In the following sections, you will find all you need to know about treating a norovirus infection.

Symptoms of norovirus infection

The common symptoms of norovirus infection are:

• Nausea
• Vomiting
• Diarrhoea

Some people may also have:

• Mild /high temperature
• Headache
• Aching arms and legs
• General tiredness and feeling “unwell”

Symptoms usually last between 2 to 3 days. Many individuals may feel and appear quite unwell while experiencing norovirus, but tend to recover quickly with adequate rest and hydration. About 40% of those infected may still show symptoms four days after they first appear.²

Who is at risk?

People of all ages can be at risk of contracting norovirus. Mortalities from norovirus are extremely rare; however, children younger than 5 years old and people with serious underlying health conditions or weakened immune systems may be significantly affected. Elderly people are particularly vulnerable and often require hospitalisation due to the high risk of dehydration. Usually, once people get infected, they will get immunity that lasts only for a few months. Hence, individuals are likely to get infected several times throughout their lives. Outbreaks could happen when people live or gather closely together in an environment like schools, child care, care homes, cruise ships, or military bases.³

How does it spread?

Norovirus is spread through the vomit or faeces (stool) of an infected person through : 

• Direct contact with vomit or faeces of an infected person
• Person-to-person contact, like when shaking hands with someone who has been sick and has the virus on their hands
• Eating contaminated foods
• Touching contaminated surfaces or objects and not washing hands
• Airborne particles are released when someone vomits⁴

Treatment options

When you or a family member has norovirus, you can typically manage the illness at home since there is no specific treatment available. Recovery usually relies on your immune system, and most people recover in about three days with no complications. It is important to focus on replacing your lost fluids and electrolytes during this time. Doctors will not prescribe antibiotics, as they are ineffective against viral infections like norovirus, since antibiotics are only used to treat bacterial infections. 

Here are some general guidelines to follow when you have a norovirus infection:

Stay hydrated

To prevent dehydration, drink lots of water, especially electrolyte-containing beverages.. If you are not able to drink, you might need to receive intravenous fluids. Water, fruit juices, sports drinks or broths are some good examples to take while you are having an infection. It is important that you drink more than you usually do. 

You may also purchase over-the-counter oral rehydration products that contain electrolytes and glucose. It is formulated especially for replacing lost fluids rapidly. Particularly, children, elderly people, people with compromised immune systems, people with severe diarrhoea, or those who exhibit signs of dehydration could take this. Consult the chemist or your doctor before giving this to your infants.⁵

Eat light and digestible foods

Not eating when you have a norovirus infection will not help you speed up the recovery process. Try to transition back into eating small amounts of food at frequent intervals; this will help when you are feeling nauseous. You may also begin to gradually eat bland food, easy-to-digest food such as soup, toast, dry cereals, oatmeal, or crackers. 

Try to limit or even avoid caffeine, alcohol, milk and dairy products, and nicotine. 

Some studies suggest that probiotics might help to shorten the diarrhoea; however, for safety reasons, please seek advice from healthcare professionals before using them.

Medications

In some cases, adults can get over-the-counter medicines to relieve the symptoms, such as loperamide or bismuth salicylate, to help treat the diarrhoea. These medicines may not be suitable for babies or children; you should seek advice from your doctor before giving any over-the-counter medicine to your child. 

Rest and recovery

Stay off school or work until at least 2 days after not being sick or having diarrhoea or after the symptoms have stopped, as this is the time that is most infectious, and also do not visit your GP or hospital while you are still symptomatic.Get plenty of rest, as it will also help you to recover. 

What to remember while you are having Norovirus

• It is important to remember that while you are infectious, you need to avoid cooking or helping others prepare meals until 48 hours after symptoms are symptom-free, as norovirus can spread through contaminated food and if someone who handled the food has a norovirus infection. 
• You also need to wash contaminated bedding or clothing at 60°C, and separately from other clothing; also, where possible, wear gloves
• It is important to disinfect any contaminated surfaces using bleach-based cleaning products

Norovirus symptoms usually happen suddenly. There is no cross-strain immunity for norovirus, and it is only short-lived immunity. Hence, you may get multiple infections if you are exposed to different strains of the virus. You will usually feel better between 2-3 days.³

Prevention

Prevention strategies include:

• Wash your hands regularly and thoroughly using soap and water, especially after using the toilet and before preparing food. Alcohol-based hand sanitisers will not help against this virus.
• You must avoid eating raw and unwashed food 
• Cook your food thoroughly- especially seafood or shellfish- or to an appropriate cooking temperature
• Clean any surfaces that you think are easily contaminated with bleach-based household cleaner
• Keep the toilet area clean and disinfect it using a bleach-based household cleaner. You also need to flush away any stool or vomit from the toilet
• Avoid sharing any towels or clothing
• Avoid any contact with anyone who has a norovirus infection

Researchers are conducting clinical trials for vaccine development. At present, no vaccines against norovirus are available due to the genetic and antigenic diversity of noroviruses, with multiple co-circulating variants of various genotypes.⁶

When to seek medical advice

You do not normally get to see your doctor when you get norovirus, as there is no specific treatment for it. However, in the UK, you may call 111 when you are worried if: 

• Your baby is under 12 months, or if they stop breast or bottle feeding when they are ill
• Your baby or someone you care for has signs of dehydration, or still has signs of dehydration after oral rehydration solutions
• Your baby or someone you care for keeps being sick and cannot take any fluids
• Bloody diarrhoea or bleeding from the bottom
• Vomiting for longer than two days or diarrhoea lasting longer than seven days

Summary

Norovirus infection is commonly associated with gastroenteritis (disease of the stomach and intestines). It is highly contagious and often leads to vomiting, diarrhoea, and abdominal pain, with some people also experiencing a fever while they are infected. While there is no specific antiviral treatment for norovirus, treatments are mainly focused on supportive care. This includes maintaining hydration through oral rehydration solutions or intravenous fluids in severe cases and addressing symptoms with antiemetics or antidiarrheals when appropriate. Currently, there are no vaccines to prevent the infection. However, there are some preventive measures that we can follow, such as practising good hand hygiene and proper food handling, which are crucial in reducing transmission. Understanding these treatment options can help mitigate the impact of norovirus outbreaks, particularly for those with high-risk populations.