Shigella infection (shigellosis)
Shigella infection (shigellosis) is a type of gastroenteritis caused by Shigella bacteria.
The symptoms of Shigella infection include fever, diarrhoea, (sometimes with blood and mucous), vomiting and stomach cramps. The disease is more severe in children and older people. The infection usually lasts for several days but can last longer. Sometimes people infected with Shigella do not have symptoms.
Shigella is very easily spread. It spreads from person to person by the faecal-oral route, by direct or indirect contact with faecal matter. This commonly occurs if hands are not washed properly, particularly after going to the toilet or changing nappies.
Certain types of sexual activity, such as oral-anal sex, allow the transmission of Shigella from person to person. Shigellosis can affect anyone. People living in conditions of poor hygiene, children, and men who have sex with men, are at greatest risk.
Shigella infections may also be acquired from eating food contaminated with the bacteria. Flies can carry Shigella and can contaminate food.
Symptoms usually develop in one to three days, although in some cases it may take up to a week. People are infectious while they have diarrhoea and until the bacteria are cleared from the bowel. Shigella can be present in a person’s faeces for some weeks after their symptoms have ceased, and the infection can still be passed on to others. Treatment with appropriate antibiotics generally reduces the time a person is infectious to a few days.
Drinking fluids to prevent dehydration is an important part of treatment. It is also important to continue eating, as this will encourage recovery. Antibiotics are usually prescribed to people who are ill and whose tests show they have Shigella.
A child with Shigella should not attend child care, preschool or school until their diarrhoea has ceased and they are found to be clear of infection on faecal specimen testing. People who work as food handlers (eg. kitchen staff and butchers) or who care for children, patients or older people (eg. doctors, nurses, child care workers) should not return to work until their diarrhoea has ceased and they are cleared of infection on faecal specimen testing. All other people with infection should not return to work or school until symptoms have ceased for 24 hours.
Good hygiene is essential to prevent the further spread of Shigella. Spread of Shigella can be prevented by:
- thorough washing of hands with soap and water for at least 10 seconds:
- after going to the toilet
- after changing nappies
- after any possible exposures to faecal material
- before handling food or caring for other people
- washing vegetables and fruit that are eaten raw
People who have shigellosis should not have sex where there is any contact with the anus, to avoid transmitting Shigella to their mouth.
Shigella can make some people (particularly young children and older people) seriously ill, while some people may 'carry' the organism in their bowels without any illness. Rarely, infection can be life threatening.
For further information please contact your local doctor or nearest public health unit.
Heymann D, (Ed). 2008. Control of Communicable Diseases Manual, 19th Ed. American Public Health Association: Washington.
Queensland Health fact sheets: