What is shigellosis?
Shigellosis is a diarrhoeal disease caused by infection with Shigella bacteria.
What are the symptoms?
Infection with Shigella usually results in diarrhoea, fever and nausea. Sometimes vomiting, and stomach cramps can also occur. Often blood or mucous is found in the faeces. The symptoms begin 1-7 days (usually 1-3 days) after exposure. Symptoms usually last 4-7 days, but can last longer. Some infected people do not have any symptoms.
How is it spread?
Shigellosis is passed 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.
Shigella infections may also be acquired from eating food or drinking water contaminated with the bacteria either through poor hand hygiene or water contaminated with sewage. Flies can transfer Shigella from human waste to uncovered food.
A person can have Shigella present in their faeces for some weeks and have no symptoms, and still pass infection on to others.
Who is at risk?
Shigellosis can affect anyone. Children, and men who have sex with men, are at greatest risk. People with poor immune systems and the elderly are at greater risk of having more severe illness.
How is it prevented?
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 travelling to countries where shigellosis is common should also:
- avoid uncooked foods, including fruit and vegetables unless you are able to peel them yourself
- drink bottled or boiled water
- not drink untreated water, including ice and drinks mixed with water
- avoid eating from street stalls
- ensure hot food is thoroughly cooked and eaten whilst hot.
People who have shigellosis should not have sex where there is any contact with the anus, to avoid transmitting Shigella to the mouth.
As Shigella is spread from person to person, people with shigellosis should not go to work while they have diarrhoea. Some people are considered to be in 'high-risk' jobs for spreading Shigella. This includes people who work as food handlers (such as kitchen staff and waiters, butchers); and those who care for patients, children or the elderly. People with shigellosis in high-risk jobs should not return to work until 48 hours after their diarrhoea has stopped.
In the home, people with shigellosis should not prepare food or care for others while they are sick. Children, particularly those in nappies, should be kept home from childcare until 24 hours after their diarrhoea has stopped.
Children and adults should not swim for 2 weeks after the diarrhoea has stopped.
How is it diagnosed?
Diagnosis of shigellosis requires the isolation of Shigella bacteria from a stool specimen. Your doctor may order this test if you have symptoms.
How is it treated?
People with shigellosis are usually prescribed antibiotics by their doctor to reduce the severity and length of illness and shorten the time for which the person is infectious to others. Drinking increased amounts of fluid is important to avoid dehydration. Young children (particularly infants) are susceptible to dehydration from diarrhoea, and parents should seek medical attention.
What is the public health response?
Laboratories are required to notify cases of Shigella to the local Public Health Unit. Public health unit staff will interview cases and their carers and try to identify the source of infection and control further cases.
For further information please call your local Public Health Unit on 1300 066 055