Park Leys Medical Practice

Norovirus - Frequently asked Questions

What are noroviruses?
Noroviruses are a group of viruses that are the most common cause of gastroenteritis (stomach bugs) in England and Wales. In the past, noroviruses have also been called ‘winter vomiting viruses’, ‘small round structured viruses’ or ‘Norwalk-like viruses’.

How does norovirus spread?
The virus is easily transmitted from one person to another. It can be transmitted by contact with an infected person; by consuming contaminated food or water or by contact with contaminated surfaces or objects. The infectious dose is very low, swallowing as few as- 100 virus particles may be enough to cause illness.

What are the symptoms?
The most common symptoms are nausea, vomiting and diarrhoea.Symptoms oftenwith the sudden onset of nausea followed by projectile vomiting anddiarrhoea.However, not all of those infected will experience all of the symptoms.people may also have a raised temperature, headaches and aching limbs.
Symptoms usually begin around 12 to 48 hours after becoming infected. The illness is self-limiting and the symptoms will last for 12 to 60 hours.Most people make a full recovery within 1-2 days, however some people (usually the very young or elderly) may become very dehydrated and require hospital treatment.

Why does norovirus often cause outbreaks?
Norovirus often causes outbreaks because it is easily spread from one person to another and the virus is able to survive in the environment for many days. There are many different strains of norovirus, immunity is short-lived and infection with one strain does not protect againstwith another strain.commonly occur in semi-closed environments such as hospitals, nursing homes, schools and on cruise ships, where people are in close contact with one another for long periods.

How can these outbreaks be stopped?
Outbreaks can be difficult to control because norovirus is easily transmitted from one person to another, its low infectious dose and becausevirus can survive in the environment for lengthy periods. The most effective way to respond to an outbreak is to institute good hygiene measures such as strict adherencehand-washing especially when handling food,after contact with infected people,afterthe toilet; disinfecting contaminated areas promptly; not allowing infected people to prepare food until 48 hours after symtpoms have elapsed and isolating ill peopleup to 48 hours after their symptoms have ceased.

How is norovirus treated?
There is no specific treatment for norovirus apart from letting the illness run its course. It is important to drink plenty of fluids to prevent dehydration.

If I’m suffering from norovirus, how can I prevent others from becoming infected?
Good hygiene is important in preventing others from becoming infected – this includes thorough hand washing after using the toilet. Food preparation should also be avoided until 48 hours after the symptoms have subsided.

Who is at risk of getting norovirus?
There is no one specific group who are at risk of contracting norovirus – it affects people of all ages. The very young and elderly should take extra care if infected, as dehydration is more common in these age groups.
Outbreaks of norovirus are reported frequently anywhere that large numbers of people congregate for periods of several days.Thisan ideal environment for the spread of the disease. Healthcare settings tend to be particularly affected by outbreaks of norovirus. A recent studythe Agency shows that outbreaks are shortened when control measures at healthcare settings are implemented quickly, such as closing wards to new admissions within 4 days of the beginning of the outbreak and implementing strict hygiene measures.

How common is norovirus?
Norovirus is not a notifiable disease so reporting isThe HPA only receives reports of outbreaks and we see anywhere between 130 and 250 outbreaks each year. It is estimated that Norovirus affects between 600,000 and a million people in the UK each year.

Are there any long-term effects?
No, there are no long-term effects from norovirus.

What can be done to prevent infection?
It is impossible to prevent infection, however, good hygiene measures (such as frequent hand washing) around someone who is infected is important. Certain measures can be taken in the event of an outbreak, including the implementation of basic hygiene and food handling measures and prompt disinfection of contaminated areas, and the isolation of those infected for 48 hours after their symptoms have ceased.