Shigellosis

You are most likely to get shigellosis from eating food or drinking water that has been contaminated by the poo (faeces) of someone with the infection. The bacteria are very contagious and it takes just a small number to contaminate food, water or objects that can then make someone sick.

Flies can also spread the bacteria by flying from human poos to uncovered food.

Shigella germs can also spread during sexual and close intimate physical activity, from the poo or unclean fingers of one person to the mouth of another. This can happen during:

• direct sexual contact, such as anal or oral sex with someone with shigellosis
• indirect sexual contact, if objects used in sexual activity are contaminated by shigella germs, such as sex toys or used condoms.

They symptoms of shigellosis usually start 1 to 3 days after you are infected. But they can happen up to 7 days later. Symptoms tend to last 4 to 7 days and include:

• runny poos, sometimes with blood
• fever
• stomach pain
• throwing up (vomiting).

You may be infected and have no symptoms, but you can still pass the bacteria to others.

Some people, especially tamariki and older people, can get very ill as they are more likely to become dehydrated. This means their body does not have enough water to function properly. They may need hospital treatment.

Contact your healthcare provider or call Healthline for advice on 0800 611 116 if you have:

• a fever
• bloody runny poos
• severe stomach cramping or tenderness
• dehydration
• severe nausea (feel very sick).

If you think you have shigellosis visit your healthcare provider. You may be asked to send a sample of your poo to a laboratory for testing.

The role of public health

Shigellosis is a notifiable disease. This means that healthcare providers or laboratories will inform public health when someone has it. This way, we can monitor how many people are sick and give advice on how to reduce its spread.

There are various types of shigellosis, and some require different kinds of treatment and management.

Most people can self-manage their symptoms at home by resting and drinking lots of fluids to avoid dehydration. However, you may require treatment with antibiotics if you are at higher risk of becoming unwell, such as:

• tamariki and rangatahi
• older adults
• people living with HIV who have a weakened immune system.

Shigellosis is highly infectious. If you have shigellosis you should stay away from school, early childhood centres or work until 2 days after the symptoms have stopped. Some of these settings may be high risk places and you will also need to meet clearance requirements before returning.

Do not go swimming in a pool if you have runny poos. You need to wait until at least 2 weeks after symptoms have gone.

Wash your hands with soapy water for 20 seconds, then dry well with a clean cloth or paper towel every time:

• after going to the toilet
• before preparing food, eating or drinking
• after changing nappies.

If you have symptoms, avoid preparing food for other people. If you must do so, wash and dry your hands well first.

High-risk places

For some types of shigellosis additional precautions are required. You may be asked to stay away from:

• workplaces that handle food or drinks
• health and aged care facilities
• schools and early childhood centres.

People can only return to high-risk places if they have met clearance requirements:

• had no symptoms for at least 48 hours
• had 2 follow-up negative poo tests after being symptom free, at least 48 hours apart.

These will check you are no longer infectious and reduces the risk of you passing shigellosis to others.

If you are not treated with antibiotics, you will need to wait until 1 month after your symptoms began and then complete testing.

Be careful with the food you eat and what you drink.

Wash your hands often and thoroughly.

Be careful around pēpi and tamariki, even in they are in nappies.

Preventing the spread of food and water borne diseases

Preventing shigellosis during sexual activity

While anyone can get shigellosis from sexual contact with someone with the infection, the risk of transmission is generally higher for men who have sex with men (MSM) and their sexual networks. This may include people of any gender or sexual identity, whether they are transgender or cisgender, and non-binary people.

The Burnett Foundation have developed information for MSM.

Shigella — Burnett Foundation

The following guidance is applicable for all adults to reduce the risk of transmission of shigellosis and some other gastroenteric infections (for example, Hepatitis A, giardia) during sexual activity:

• wash your hands, genitals and anus before and after sex or sexual activity
• do not have sex if you have diarrhoea
• use condoms or dentals dams during anal and oral sex
• use soap and warm water to clean any objects used in sexual activity after use and/or between individuals (for example, sex toys).

Cleaning your toys — Burnett Foundation

Travel advice to prevent shigellosis

If you are travelling to countries where shigella is more common you can reduce your risk of infection. 

• Avoid unsafe drinking water, including ice and drinks mixed with water.
• Only drink bottled water and boiled water.
• Avoid food from street stalls.
• Make sure hot food is well cooked and eat it while it is hot. 
• Make sure you wash and dry your hands after going to the toilet, and before preparing food or eating and drinking.