Shigella infection and dysentery
- Shigella infection (also known as shigellosis) causes diarrhoea, which is mostly spread from person to person.
- The best way of preventing shigellosis is by washing hands especially before eating or preparing food.
- Most people with shigellosis recover by themselves, but if required, can be treated with antibiotics.
Shigellosis is an infection of the digestive tract (or gut) caused by Shigella bacteria. It usually results in diarrhoea, which can be severe.
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.
Who is at risk?
Anyone can get shigellosis. People at higher risk include children, travellers to developing countries, residents of WA remote communities and men who have sex with men.
What are the signs and symptoms?
Symptoms start between 1 to 7 days (usually 1 to 3 days) after infection and typically last for between 4 to 7 days.
Symptoms can include:
- diarrhoea (often with blood or mucus)
- §nausea and vomiting
- fever
- stomach cramps.
How do you know if you have it?
There are many causes of gastroenteritis, and laboratory testing of a faecal specimen is necessary to confirm that symptoms are due to Shigella infection.
How is it treated?
People with shigellosis should:
- drink plenty of fluids such as plain water or oral rehydration drinks to avoid dehydration. Dehydration is especially dangerous for young children and the elderly.
- avoid anti-vomiting or anti-diarrhoea medications unless prescribed or recommended by a doctor.
Most people with shigellosis recover by themselves and do not need antibiotic treatment. However, if diarrhoea continues for more than a week or is causing dehydration or weight loss, contact a doctor as treatment may be required.
Some groups of people with shigellosis may need treatment as they are more likely to spread the infection to other people because of their age or where they live. This includes children under 6 years old, residents in aged care facilities or people living in WA remote communities.
Occasionally, people are infected with Shigella bacteria that are resistant to several commonly available antibiotics. These are called multi-drug resistant (MDR) bacteria, which may require special antibiotic treatment. Men who have sex with men and overseas travellers are more likely to have MDR Shigella bacteria and should speak to their doctor about specific treatment.
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 healthcare, residential care, childcare, or are paid to prepare or handle food.
- Wash and dry your hands before preparing food and after going to the toilet.
- Avoid preparing or handling food and drinks for other people until at least 24 hours after your symptoms have finished.
- Immediately wash any clothes or bedding contaminated with diarrhoea or vomit using detergent and hot water.
- Immediately clean contaminated hard surfaces (for example, benches, floors and toilets) using detergent and water. followed by disinfection using a diluted bleach-based product.
- Avoid sexual contact for 7 days after diarrhoea has stopped.
- If any close contacts (including sexual partners) also have diarrhoea, advise them to see a doctor and get tested.
How can it be prevented?
- Avoid close contact with people who have diarrhoea or vomiting.
- Wash and dry your hands thoroughly after changing nappies, going to the toilet, cleaning up vomit or diarrhoea, and before eating, drinking or preparing food or drink. If hand-washing facilities are not available, use an alcohol-based gel.
- Wash your hands with soap and water after sexual contact and handling condoms or sex toys. Use of condoms and dental dams are the best way to protect you from infections.
- When travelling in developing countries, you should not eat or drink:
- salads and fresh fruit juices
- raw or cold seafood, including shellfish
- raw or runny eggs
- cold meat
- unpasteurized/raw milk and dairy products
- ice in drinks or flavoured ice blocks.
You should drink bottled water or disinfect water (by boiling, chemical treatment or purifiers) for drinking and brushing teeth.
Read more about healthy international travel (external site).
Where to get help
Remember
- 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).
Last reviewed: 08-09-2021
Acknowledgements
Public Health
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.