Shigella infection (shigellosis)

Shigella infection (shigellosis) is a type of gastroenteritis caused by Shigella bacteria.

Signs and symptoms

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.

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

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 sometimes prescribed to people who are ill and whose tests show they have Shigella.

Transmission

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, or through sexual contact that involves the anus. Shigella can affect anyone, however children, people living in conditions of poor hygiene, and men who have sex with men (MSM) have the highest risk of contracting the infection.

Shigella infections may also be acquired from eating food contaminated with the bacteria. Flies can carry Shigella and can contaminate food.

Prevention

All people with Shigella infection should be excluded from work, school or childcare until 48 hours after diarrhoea has ceased. People who are infected with a particular type of Shigella called Shigella dysenteriae will need to have a further faeces test to ensure the infection has been cleared before returning to work, school or childcare. Cases should be advised not to prepare food for others or take care of children or the elderly whilst unwell.

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, rubbing hands together for at least 20 seconds:
    • after going to the toilet
    • after changing nappies
    • after any possible exposures to faecal material
    • before handling food or caring for other people
    • before washing vegetables and fruit that are eaten raw.

  • People who have shigellosis should not engage in sexual activity where there is contact with the anus to avoid transmitting Shigella to their own or someone else's mouth. This includes handling used sex toys or condoms, or touching and infected person's anus with their mouth or fingers.

Health outcome

Shigella can make some people seriously ill, particularly young children and older people. Some people may 'carry' the organism in their bowel without any illness. Shigella infection can be life threatening but this is very rare and the majority of people recover quickly and completely from illness.

Other resources

Related Content

Queensland Health fact sheets:

MSM-specific health advice for sexually transmitted infections

Help and assistance

For further information please contact your local doctor or nearest Public Health Unit.

If you are in an emergency situation, call 000

Contact

Get qualified health advice 24/7 for the cost of a local call. 13 HEALTH (13 43 25 84)

References

Heymann,DL. (2015). Control of Communicable Diseases Manual, 20th edition. Washington, DC: American Public Health Association.