Shiga toxin-producing E. coli (STEC)
Shiga toxin-producing E. coli (STEC)
Escherichia coli (E. coli) are bacteria found in the environment, in food, and in the intestines of animals and people. Most types of E. coli are harmless and are an important part of a healthy digestive tract. However, some can make you unwell.
E. coli can be divided into 2 groups:
- those that can produce Shiga toxin, known as Shiga toxin-producing E. coli (STEC) this includes E. coli O157
- those that can't produce Shiga toxin
STEC are known to cause more severe illness than E. coli that doesn't produce Shiga toxin. STEC can cause severe stomach pain, bloody diarrhoea and kidney failure.
Common Symptoms
⚠️ This symptom list is for educational purposes. Having these symptoms does not mean you have this condition. See a doctor for proper diagnosis.
Medicines Commonly Used
⚠️ These medicines are commonly used for confirmed diagnoses of this condition. This is NOT a recommendation or prescription. Treatment must be determined by your doctor.
No medicines have been linked to this condition yet.
When to See a Doctor
If you or your child has bloody diarrhoea, contact your GP practice urgently. If the practice is closed, phone 111.
Contact your GP practice (not urgently) if you or your child has diarrhoea and any of the following apply:
- it is unusually frequent or severe
- it has lasted more than 7 days
- vomiting has lasted more than 2 days
- you keep being sick and cannot keep fluids down
- there is a severe or continuous stomach ache
- there has been noticeable weight loss
- a large amount of very watery diarrhoea has been passed
- there are signs of dehydration, such as dark, strong smelling urine or passing urine less often than usual
If you have a child under 12 months old and are concerned, you should contact your GP.
Causes
What causes STEC infection?
STEC infection is not a common cause of gastroenteritis, but it can be picked up in a few different ways.
Contaminated food
Food can carry STEC bacteria, and infection can happen through:
- eating food that hasn't been cooked or reheated properly all the way through
- eating raw vegetables and salad leaves
- handling contaminated food, such as raw meat or vegetables
It's a good habit to wash all vegetables, including salad leaves, before eating them. Washing helps lower the risk of infection, but it cannot remove the risk completely.
Unpasteurised dairy products
Unpasteurised milk and other dairy products may contain harmful bacteria, including STEC. People with a weakened immune system are especially vulnerable and face a higher risk if they consume these products. This includes:
- people aged 65 years or older
- pregnant women
- infants and small children
- people with a condition that weakens the immune system, such as HIV
Contaminated water
Contaminated water is another route for STEC infection, through:
- drinking water from supplies that haven't been treated adequately
- drinking water from streams, rivers and lakes
- swimming or playing in contaminated water, such as ponds or streams
Contact with animals
Being in close contact with animals, and with the places where they live, can also lead to STEC infection, particularly with cattle, sheep and goats. The bacteria are found in animal faeces (poo) and may also be present in animal saliva. Infection can be picked up through close contact with:
- animals themselves
- animal pens
- surfaces contaminated with animal poo, even when it isn't visible
During visits to farms, STEC infection can also spread through:
- contact with footwear or clothing that has become contaminated
- eating or drinking while still in close contact with animals, so it's important to wash your hands after touching animals or their surroundings and before handling any food
Contact with an infected person
Infection can also pass from person to person through poor hand hygiene, such as:
- not washing hands properly after using the toilet
- not washing hands properly after changing nappies
- not washing hands properly before handling food
Treatment
There's no specific treatment for STEC infection, and most people manage their symptoms at home and recover without medical care. That said, it can sometimes turn serious enough to need hospital admission.
What you can do
Drink plenty of fluids, since diarrhoea can lead to dehydration.
Antibiotics aren't usually recommended, as they may raise the risk of complications.
Anti-diarrhoeal drugs like loperamide (Imodium) also aren't usually recommended, since they may keep the toxin in your body longer.
See our guides on caring for a child with gastroenteritis and caring for an adult with gastroenteritis.
Prevention
Strict hygiene measures are essential to stop others getting infected.
Do
- clean your hands thoroughly with soap in running water and dry them completely; use liquid soap and warm water if you can
- always clean your hands after contact with an infected person, their clothes or bedding
- also clean your hands after any cleaning activities, including handling laundry and waste disposal
- clean your hands after going to the toilet or changing babies' nappies, and before preparing, serving or eating food
- clean your hands after contact with animals or their environment
- wash any clothing or bedding that has poo or vomit on it separately on a hot wash
- wipe down the outside of the washing machine with hot water and detergent after any heavily soiled load
- clean toilet seats, flush handles, taps, surfaces and door handles with disinfectant at least daily, more often if possible
- disinfect any surfaces or objects that could be contaminated; it's best to use a bleach based household cleaner
- deal with any spillage of poo immediately by cleaning the soiled area with hot water and detergent, ideally using gloves, then washing your hands thoroughly
- dispose of cloths by placing them in a plastic bag, sealing the neck and placing in household waste
- clean animal poo from footwear or buggy wheels after visits to animal attractions and wash your hands after doing so
Don't
- do not prepare food for others until 48 hours after your symptoms have stopped, if possible
- do not share towels or nappy changing mats
- do not bring soiled items into the kitchen to clean them, if possible
If you wear gloves while cleaning, disposable gloves should be single use only and disposed of appropriately after use. Reusable gloves should be thoroughly cleaned after each use and allowed to dry. Even if gloves have been worn during cleaning, always wash your hands thoroughly after you have removed or cleaned your gloves.
Returning to work or school
Anyone who has had a STEC infection should stay away from work or school until they have been completely free of symptoms for 48 hours.
Most people are no longer infectious after about a week. However, some people, particularly children, may carry STEC for several months after they have got better. This means they would still be infectious and able to pass it on to others.
Some people need to take special care before returning to work or school. This is because they are at higher risk of passing on the infection to others because of the nature of their job or their age.
People that work in higher risk fields
Ask your local health protection team when it is safe to return to work if:
- you work in health or social care
- you work in a childcare setting
- your work involves handling food
You will be asked to provide stool (poo) samples to show you no longer have the infection. This advice applies to people who have been:
- infected with STEC
- told they have been in close contact with someone who is infected with STEC
Children aged 5 years or younger
Speak to your local health protection team or GP about when it is safe for your child to return to school or nursery. Your child will need to provide stool (poo) samples to show they are no longer infected with STEC if they are aged 5 years or younger and have:
- had STEC
- been told they are a close contact of someone with STEC, or there are concerns about the hand hygiene of an older child
They will also need test results showing they are no longer infected with STEC before they can:
- swim in public swimming pools
- share paddling pools with others
- go to soft play areas and similar premises
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