Gastroenteritis for health professionals

Gastroenteritis is a term used for inflammation or infection of the digestive tract.

Causes of gastroenteritis

There are many causes of gastroenteritis. The commonest causes are infectious organisms such as certain bacteria, viruses and parasites. Examples include:

  • Bacteria - Salmonella, Campylobacter
  • Viruses - Norovirus, Rotavirus
  • Parasites - Giardia, Cryptosporidium

A less common cause of bacterial diarrhoeal illness is Clostridium difficile which causes gastrointestinal illness associated with the administration of antibiotics.

Mode of transmission

In general, people acquire gastrointestinal illness by:

  • direct person to person transmission
  • airborne spread through aerosolised vomit
  • consumption of contaminated food or water
  • contact with contaminated environmental surfaces or fomites (objects).

While it can be difficult initially to determine if gastrointestinal disease is foodborne or due to person-to-person spread without laboratory confirmation of the pathogen, there are features of bacterial infections that typically differ from features of viral infection.

  • Bacterial gastroenteritis is often foodborne and typically causes symptoms of diarrhoea (that may contain blood, mucus or pus), abdominal cramping and vomiting. Fever may be present.
  • Viral gastroenteritis is often spread person-to-person and is less likely to cause fever or bloody diarrhoea. It is frequently of short duration (from 24 to 48 hours). Viral gastroenteritis outbreaks in facilities (for example aged care or hospitals) can occur.

In Australia, outbreaks of gastroenteritis in settings such as aged care facilities are common. The majority of these outbreaks are viral (frequently caused by norovirus) and are usually due to person-to-person transmission.

Symptoms of gastroenteritis

Common symptoms include diarrhoea, vomiting, nausea and abdominal cramps. Sometimes these symptoms may be accompanied by fever, headache and overall weakness.

Who is at risk?

Although most cases of gastroenteritis are self-limiting, people most at risk of developing complications and who are more likely to require hospitalisation due to gastroenteritis include:

  • infants
  • young children
  • immunocompromised people and
  • the elderly.


Faecal (or if unavailable, vomitus) testing is recommended to identify the cause. Testing may be by one or more of the following:

  • microscopy
  • culture
  • nucleic acid testing (PCR).

Incubation period

Varies depending on the pathogen but may range from a few hours to several days.


There is no specific treatment for most forms of infective gastroenteritis. It is generally a self-limiting illness. In infants and elderly persons, the most common complication is dehydration so maintaining good fluid intake is important.


For most types of gastroenteritis, exclude from child care, preschool, school and work until there has been no diarrhoea for at least 24 hours. If working in a commercial food setting, the exclusion period is 48 hours.


Careful attention to standard precautions and personal hygiene is important in the prevention of gastroenteritis. Key actions for staff and residents include:

  • careful attention to hand hygiene before and after patient/resident care
  • wash hands after using the toilet, and before preparing or eating food
  • clean and disinfect surfaces used for food preparation

Notifying gastroenteritis to SA Health

In South Australia gastroenteritis caused by some specific pathogens and suspected food poisoning are notifiable to the Communicable Disease Control Branch (CDCB) (PDF 72KB) of the Department for Health and Ageing, under the South Australian Public Health Act 2011. This requirement applies to both the medical practitioner and laboratories.

Resources for health professionals

Gastroenteritis outbreaks management guideline for South Australian residential environments

SA Health has developed a comprehensive guideline, including tools to assist in the investigation of outbreaks in residential care settings (PDF 272KB)

This practical guide to the management of gastroenteritis has been developed to assist all residential environments such as residential aged care facilities (RACF) to manage outbreaks of viral and/or bacterial gastroenteritis.  The guidance provided in this document can also be applied to other health and non-health settings, including hospitals, hostels, rehabilitation facilities and cruise ships.

While this practical guide to management of gastroenteritis is aimed at residential facilities, the principles are applicable to all settings (e.g. schools, child care centres and pre-schools) and should guide decision making in all circumstances.

Clostridium difficile infection (CDI)

A Clostridium difficile fact sheet (PDF 90KB) for health care professionals describing C. difficile infection, its epidemiology, mode of transmission and prevention. For more information on CDI, see the Clostridium difficile infection (CDI) web page.

Prevention and management of infection in healthcare settings

Information about the practices that form the basic measures to prevent transmission of infectious diseases within health care environments.

Patient information

Fact sheets

For patients about the cause, signs, symptoms, treatment and prevention

You've Got What?

You’ve Got What? is a collection of patient fact sheets on a number of things including:

  • hand hygiene
  • preventing food poisoning at home
  • Blastocystis infection
  • cholera
  • Cryptosporidium infection
  • food poisoning
  • Giardia infection
  • Shigella infection
  • Yersinia infection