Norovirus is a group of viruses that cause gastroenteritis (inflammation of the gastrointestinal tract). This leads to symptoms of vomiting and diarrhoea, which is why norovirus is also known as the vomiting bug.
- Causes nausea, vomiting and diarrhoea
- Particularly prevalent in winter
- Self-help methods can alleviate symptoms
If you think you may have norovirus and would like some advice about how to manage the condition, you can speak to one of our UK doctors via our private online video consultation service.
Norovirus denotes a group of viruses that cause gastroenteritis, which leads to nausea, diarrhoea and vomiting. It is the most common virus leading to gastroenteritis in the UK.
The virus is the leading cause of nonbacterial gastroenteritis. One study claims that it accounts for up to 12% of all diarrhoea cases in developed countries. In the US, it's estimated that norovirus causes around 21 million cases of gastroenteritis each year, which in turn leads to between 56,000-71,000 hospitalisations and between 570-800 deaths. It can be contracted at any time of year; however, it's most common during winter.
The condition is very contagious, and it only takes a few viral particles to infect an individual. They are transmitted via consumption of contaminated food or water, or by being spread from person to person. The incubation period is between 12-48 hours. When someone vomits as a consequence of the virus, a large number of particles are spread onto surfaces and they can survive on these surfaces for a long period of time. Infection can occur several times in someone’s life, as immunity to the virus is specific to whatever strain it may be. Norovirus also has the ability to manipulate itself genetically.
The most common complication of the condition is dehydration, and an electrolyte imbalance in the body. Due to the sickness that accompanies the norovirus, water and salts are lost in faeces and vomiting, and if they’re not adequately replaced, dehydration will likely occur. In rare cases, dehydration can become severe and even lead to a drop in blood pressure, which reduces the flow of blood to vital organs. A less common complication is lactose intolerance. This can occur when the stomach lining is damaged, resulting in a lack of lactase, which the body needs to digest the lactose from milk.
There are several measures that can be taken to prevent the spread of norovirus. It is vital to wash hands thoroughly after using the toilet and before using kitchen utensils. In general, it's preferable not to prepare food for someone else for at least a few days if you have contracted the virus. Furthermore, surfaces and toilets should be sprayed with disinfectant regularly, especially whilst vomiting is still occurring.
It's advisable not to go to work if you have norovirus, as this could lead to spreading the infection very quickly to others.
If you have symptoms of the virus and would like to speak to a healthcare professional, our doctors may be able to help. By booking an appointment to use our private online video consultation service, you will be able to talk to a doctor about how to manage the symptoms of the norovirus and whether your symptoms warrant further medical attention. Our doctors are available at a time that best suits you.
How is norovirus diagnosed?
Norovirus can be diagnosed easily having identified its clinical symptoms. It causes nausea initially, followed by diarrhoea and vomiting. Less common symptoms are a fever, headache and aching muscles. The symptoms will usually pass in two to four days. However, it is possible for them to last longer; in these circumstances, you should speak to a doctor.
Will I need tests?
You won’t normally need to have tests if a doctor strongly suspects you have norovirus. If symptoms are persistent, a doctor can take a stool sample to reveal the source of the infection, and rule out other conditions. This is not however common practice, as the condition usually resolves within a few days.
What will a doctor normally advise?
A doctor will recommend that you stay as hydrated as possible, to remove the possibility of complications. It is encouraged to maintain good hygiene whilst you have the virus to avoid passing the infection on to others. This includes washing hands before touching food, ensuring the cleanliness of surfaces, and washing clothing or dirty linen separately from other washing. When someone’s appetite is beginning to return, it's vital to refrain from consuming food or drink in large quantities, but rather eat smaller meals that are easy to digest. Some people find the BRAT (banana, rice, applesauce, and toast) diet beneficial, because the foods are bland and allow the stomach to settle.
What treatments are there for the norovirus?
There are no specific treatments for the norovirus, as it is a self-limiting condition that the immune system can clear by itself. Whilst the infection is being cleared, it is important to stay hydrated to prevent the possibility of complications. You can do this by drinking plenty of fluids (not too quickly, as drinking too much in a short space of time can induce vomiting). Paracetamol and Ibuprofen can also help to alleviate headache and fever symptoms.
How is norovirus treated?
There is no vaccine that has been developed to prevent norovirus, and it cannot be treated with any specific medication once it has been contracted. However, the virus is a self-limiting condition and passes within a few days. It's vital to stay hydrated during this period and rest to ensure a full recovery.
What treatments are there?
There are no specific medications available to treat it besides ibuprofen and paracetamol, which can alleviate symptoms of a headache or fever. It can help to use oral rehydration therapy, where water is drunk with a combination of sugar and salts stirred in, to counter the effects of diarrhoea and vomiting.
Can I consult a doctor about food poisoning online?
Yes. You can speak to one of our doctors via our private online video consultation service. Our UK prescribers are available at a convenient time for you.