This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

Norovirus gastroenteritis

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

Acute gastroenteritis is a common ailment in humans and remains a major public health concern worldwide. Norovirus, a member of the genus Norovirus, in the family Caliciviridae, is considered to be a common cause of outbreaks and sporadic cases of acute gastroenteritis among all age groups.

Reservoir:

  • gastrointestinal tract of humans
  • capable of surviving in the environment

Epidemiology:

  • commonest cause of gastroenteritis in England and Wales
  • increased prevalence during colder months
  • persons of all ages are at risk from infection. The elderly and very young are at greater risk of developing dehydration
  • most people with Norovirus do not access health care services. Outbreaks are very common in semi-closed environments such as schools, hospitals and nursing homes.

Transmission occurs by ingestion of contaminated food or water, exposure to contaminants (fomites, aerosolized vomitus), and person-to-person contact.

  • known to have high transmissibility and a low infectious dose, Norovirus has been recognized as the primary source of outbreaks in a range of environments, including nursing homes, hospitals, schools, hotels, and cruise ships

Incubation period:

  • usually 12-62 hours, rarely 6-84 hours

Noroviruses can be divided into five genogroups based on the genome sequence of the RNA-dependent RNA polymerase and the capsid regions

  • of the five identified genogroups, three distinct strains (GI, GII, and GIV) have been associated with human gastroenteritis,

Clinical features:

  • symptoms of a norovirus usually start between 24-48 hours after the initial infection, although they can start after as little as 12 hours. The first symptom is usually a sudden onset of nausea, which is followed by projectile vomiting and watery diarrhoea
  • some people may also have:
    • a mild fever
    • headaches
    • abdominal cramps, or
    • myalgia
  • in rare cases of the norovirus, seizures can occur
  • symptoms normally last between 12-60 hours, although most people make a full recovery within one to two days. However, the diarrhoea may last slightly longer

Infectivity:

  • whilst symptomatic and for 48-72 hours after diarrhoea has stopped.

Management:

  • no specific treatment
  • ensure adequate fluid intake; paracetamol if fever or headaches

Notes:

  • the ease of person-to-person transmission, low infectious dose and ability to survive in the environment for several days all contribute to the high number of outbreaks caused by Norovirus
  • immunity is short-lived; infection with one strain of Norovirus is not protective against other strains.

Reference:


Create an account to add page annotations

Add information to this page that would be handy to have on hand during a consultation, such as a web address or phone number. This information will always be displayed when you visit this page

The content herein is provided for informational purposes and does not replace the need to apply professional clinical judgement when diagnosing or treating any medical condition. A licensed medical practitioner should be consulted for diagnosis and treatment of any and all medical conditions.

Connect

Copyright 2024 Oxbridge Solutions Limited, a subsidiary of OmniaMed Communications Limited. All rights reserved. Any distribution or duplication of the information contained herein is strictly prohibited. Oxbridge Solutions receives funding from advertising but maintains editorial independence.