Shiga toxin E. coli (STEC) and Haemolytic Uraemic Syndrome (HUS) fact sheet

What are STEC infections and HUS?

Escherichia coli (E. coli) is a bacteria that can be found in the intestinal tract of humans and animals. Most of these bacteria are not harmful. However, some types, such as Shiga toxin-producing E.coli (STEC), produce toxins which can cause illness.

A small number of people with STEC infection may develop haemolytic uraemic syndrome (HUS). HUS is characterised by kidney failure, bleeding and anaemia (due to destruction of the red blood cells that carry oxygen around the body). Children under 5 and the elderly are at greatest risk of developing this condition. This syndrome can also be caused by other types of bacteria and medical conditions.

What are the symptoms?

Symptoms of STEC infection include abdominal pain and watery or bloody diarrhoea. Vomiting and fever may occur. Symptoms can begin anywhere between 2 to 10 days but usually 3 to 4 days after ingesting the bacteria and last for 5 to 7 days. Infection may sometimes cause no or very mild symptoms.

Signs and symptoms of HUS can include fatigue, decreased urination, bruising or a rash with fine spots, swelling of limbs, high blood pressure, jaundice (yellowish discolouration of the skin and the whites of the eyes), and reduced consciousness and seizures. 

How is it spread?

STEC is carried by animals, such as cows and sheep. People are infected when they ingest the faeces of an infected animal or person, either directly or indirectly. The common sources of STEC infections include:

• Eating undercooked beef or lamb mince (for example in hamburgers)
• Drinking unpasteurised milk
• Eating contaminated fresh produce, such as salad vegetables.
• Eating uncooked meat products (for example mettwurst and salami)
• Swallowing contaminated water
• Contact with farm animals and cattle, and their faeces

STEC can be spread from one person to another through contact with faeces of an infected person either directly by close personal contact or indirectly by touching contaminated surfaces such as nappies. People are generally infectious for one week or less. Occasionally people can remain infectious for longer, especially children, without showing any symptoms and still pass the infection to others.

How is it diagnosed?

Diagnosis of STEC infection is made when your doctor asks for a stool (faeces) specimen which is sent to a pathology laboratory and the bacteria or toxin is detected. Diagnosis of HUS depends on blood test and examination of the patient.

How is it treated?

Most people with mild illness recover without any specific treatment. Antibiotics are generally not recommended as they may increase the risk of HUS.

People with confirmed or suspected STEC infection should drink plenty of fluids to avoid dehydration. Dehydration is especially dangerous for babies and the elderly. Medicines to prevent vomiting or diarrhoea should not be given (especially in children) except when specifically prescribed by a doctor.

If you experience severe or prolonged symptoms you should visit a doctor. 

HUS is a serious condition that requires treatment in a hospital intensive care unit. Kidney dialysis and blood transfusions may be necessary.

How is it prevented?

To help prevent infection with STEC and the development of HUS: 

• Wash hands thoroughly with soap and running water after contact with animals and handling pet food, toys and bedding., 
• Wash hands thoroughly with soap and running water before preparing or eating food, after using the toilet and changing nappies.
• Keep raw foods separate from cooked and ready-to-eat foods (for example salads) to prevent cross-contamination. Store raw meat below ready-to-eat food in the refrigerator and use separate chopping boards and knives for raw and ready-to-eat foods.
• Thoroughly cook meat, especially minced meat (such as burgers and sausages) to 75°C or above. 
• Keep cold food below 5°C and hot food above 60°C
• Thoroughly wash all fruit, vegetables and salad ingredients that are intended to be eaten raw
• Consume only pasteurised milk or milk products, such as cheese, ice cream, and yogurt
• Don’t drink untreated water from lakes, rivers or streams

How is it controlled?

People with gastro symptoms should not attend work school or childcare while ill and until there has been no diarrhoea for 24 hours.

People with diarrhoea who are involved in food preparation for a food business should not work while they are ill and should not return to work until 48 hours after their diarrhoea have ceased. 

People with gastro symptoms should maintain good hygiene practices until 24 hours after diarrhoea ceases, including:

• Washing hands thoroughly with soap and running water after using the toilet, before preparing or eating food after cleaning or contact with soiled items
• Don’t prepare or handle food for other people
• Don’t provide personal care to others
• Don’t share utensils, towels, linen or personal items with others
• Don’t swim in any pools or other water bodies 

Doctors, hospitals and laboratories must notify cases of STEC and HUS to Public Health Services. Public Health Services will work with the doctor, the patient or the patient's family to identify possible sources of infection, prevent further infections and educate the public. 

For more information contact the Public Health Hotline on 1800 671 738.