What is norovirus? (Diarrhoea and vomiting bug) | NHS

What is Norovirus? (Diarrhoea and Vomiting Bug)

Introduction

Norovirus, often referred to as the "winter vomiting bug," is a highly contagious virus that causes gastroenteritis, an inflammation of the stomach and intestines. It is one of the leading causes of diarrhoea and vomiting outbreaks, particularly during the colder months. This virus can affect people of all ages and is notably problematic in communal settings such as hospitals, schools, and care homes.

Symptoms

The primary symptoms of norovirus include sudden onset of nausea, projectile vomiting, and watery diarrhoea. Some people may also experience mild fever, headache, stomach cramps, and muscle aches. Symptoms typically begin 12 to 48 hours after exposure to the virus and can last between one to three days. In some cases, dehydration can occur, especially in vulnerable populations such as the elderly and young children.

Transmission

Norovirus is highly infectious and spreads rapidly through contact with contaminated food, water, surfaces, or an infected person. Consuming food prepared by someone with the virus, touching contaminated surfaces, or close contact with an infected individual can lead to infection. The virus is resilient and can survive on surfaces for days, making it crucial to maintain good hygiene practices.

Prevention

Preventing the spread of norovirus involves rigorous hygiene and sanitation measures. Wash hands thoroughly with soap and water, particularly after using the toilet and before eating or preparing food. Disinfect surfaces, especially in high-touch areas like kitchens and bathrooms, with effective cleaning agents. If you are infected, stay at home and avoid preparing food for others until at least 48 hours after symptoms have ceased to prevent spreading the virus.

Treatment

There is no specific treatment for norovirus; management focuses on relieving symptoms and preventing dehydration. Drink plenty of fluids to replace lost electrolytes—solutions like oral rehydration salts are particularly effective. Clear fluids such as water, broths, and diluted fruit juices are advisable. Over-the-counter medications may help alleviate symptoms, but it is vital to consult a healthcare professional if symptoms persist or worsen.

When to Seek Medical Help

While most cases of norovirus resolve without complications, certain symptoms necessitate medical attention. Seek help if you experience severe dehydration signs (e.g., excessive thirst, decreased urination, dizziness), prolonged symptoms lasting more than three days, or if a vulnerable person (infant, elderly, or those with compromised immune systems) is affected. The NHS provides resources and guidance on managing symptoms and when to seek care.

Conclusion

Norovirus is a common but preventable cause of gastroenteritis. By understanding the symptoms, modes of transmission, and prevention strategies, individuals can significantly reduce their risk of infection. Adhering to good hygiene practices and timely medical consultation can help manage and control outbreaks, ensuring better public health outcomes in the UK.