Shigella infection and dysentery
What is Shigella infection?
Shigella infection (also known as shigellosis) is an infection of the digestive tract (or gut), caused by Shigella bacteria.
These bacteria are only found in humans and other primates. There are a number of types of Shigella.
Shigella dysenteriae causes the most serious illness, and you are more likely to catch this while travelling to developing countries.
Read more about healthy international travel.
How do you get Shigella infection?
You become infected with Shigella by ingesting the bacteria through your mouth. This can be by drinking or eating something contaminated with Shigella bacteria.
Person-to-person spread of Shigella can also happen if you come into contact with microscopic amounts of faeces (poo) from an ill person. Such spread may occur directly by close personal contact, or indirectly by touching contaminated surfaces such as taps, toilet flush buttons, toys and nappies. Shigellosis can also be spread through oral-anal sex.
You only need to take in a small number of these bacteria to become ill.
Signs and symptoms
Symptoms start between 1 to 7 days (usually 1 to 3 days) after you have ingested the bacteria and typically last for between 4 to 7 days.
Symptoms can include:
- dysentery (diarrhoea containing mucus and/or blood)
- nausea and vomiting
- stomach cramps.
How do I know I have Shigella infection?
There are many causes of gastroenteritis, and laboratory testing of a faecal specimen is necessary to confirm that symptoms are due to Shigella infection.
Treatment of Shigella infection
People with confirmed or suspected Shigella infection should:
- Drink plenty of fluids such as plain water or oral rehydration drinks (available from pharmacies) to avoid dehydration. Dehydration is especially dangerous for babies and the elderly.
- Avoid anti-vomiting or anti-diarrhoeal medications unless prescribed or recommended by a doctor.
Antibiotics may be required to relieve symptoms and reduce the risk of infecting other people. Consult your doctor.
If you experience severe or prolonged symptoms you should visit a doctor.
While you have the infection
- Do not go to work or school for at least 24 hours after symptoms have finished, or 48 hours if you work in or attend a high risk setting, such as health-care, residential care or child-care, or handle food as part of your job.
- If you have Shigella dysenteriae infection and work in a high risk setting, as described above, you may be contacted by the local public health unit to discuss extra precautions.
- Wash and dry your hands thoroughly after going to the toilet.
- Avoid preparing or handling food and drinks for other people in your household until at least 24 hours after your symptoms have finished. If you must prepare or handle food, thoroughly wash your hands beforehand to reduce the risk of spreading the infection to others.
- Immediately remove and wash using detergent and hot water any clothes or bedding contaminated with vomit or diarrhoea.
- After an episode of diarrhoea or vomiting, clean contaminated surfaces (for example benches, floors and toilets) immediately using detergent and hot water. Then disinfect surfaces using a bleach-based product diluted according to manufacturer’s instructions.
- Clean carpet or soft furnishings contaminated with diarrhoea or vomit immediately using detergent and hot water and then steam clean.
How can Shigella infection be prevented?
- Avoid contact with people who have gastroenteritis symptoms.
- Wash and dry your hands thoroughly after changing nappies, going to the toilet, cleaning up vomit or diarrhoea and before eating or drinking. If hand-washing facilities are not available use an alcohol-based gel.
- Keep cold food below 5 °C and hot food above 60 °C.
When travelling to developing countries, especially in Asia, the Pacific islands, Africa, the Middle East and Central and South America you should avoid:
- salads and fresh fruit juices
- raw or cold seafood, including shellfish
- raw or runny eggs
- cold meat
- unpasteurised milk and dairy products (including ice-cream)
- ice in drinks and flavoured ice blocks.
Fruit that you peel yourself is usually safe. Remember – ‘cook it, boil it, peel it, or leave it’.
Use bottled water or disinfect water (by boiling, chemical treatment or purifiers) for drinking and brushing teeth.
Read more about healthy international travel.
Where to get help
- See your doctor
- Visit a GP after hours
- Ring healthdirect on 1800 022 222
- Shigella bacteria are mainly found in humans, so person-to-person spread is most common.
- You only need to ingest a small number of these bacteria to become ill.
- Shigella dysenteriae is most often seen in people who have travelled to developing countries.
View and download this information as a PDF factsheet (123KB).
This publication is provided for education and information purposes only. It is not a substitute for professional medical care. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your healthcare professional. Readers should note that over time currency and completeness of the information may change. All users should seek advice from a qualified healthcare professional for a diagnosis and answers to their medical questions.