E. coli infection

5 min read

An E. coli infection can cause diarrhoea, blood in poo, vomiting, stomach cramps, and fever.

The bacterial infection is mainly caused by the E. coli O157 strain, found in the gut and poo of many animals, particularly cattle and sheep.

This page covers:

  • causes
  • symptoms
  • treatment
  • prevention
  • returning to work or school

Causes of an E. coli infection

An E. coli O157 infection can be caught by:

  • eating infected food, such as raw leafy vegetables, undercooked meat, or raw milk products
  • touching infected animals or accidentally coming into contact with their poo, like at petting farms and campsites
  • contact with infected people, particularly if you don't wash your hands thoroughly after using the toilet or before handling food
  • drinking water from poorly treated water supplies
  • swimming or playing in infected water, such as ponds or streams

Symptoms of E. coli

People with an E. coli O157 infection may have one or more of these symptoms:

  • diarrhoea
  • blood in poo
  • vomiting
  • stomach cramps
  • fever

People usually notice symptoms 3-4 days after they've been infected, but symptoms can start any time between 1 and 14 days afterwards.

These symptoms can last up to two weeks.

A small number of people with E. coli go on to develop a serious condition called haemolytic uraemic syndrome (HUS).

This can sometimes lead to kidney failure. The risk of HUS is highest in children aged under five years.

Some people are infected with E. coli O157 but don't get any symptoms.

Find out more about treating

diarrhoea and vomiting

Treating E. coli

There's no specific treatment for an E. coli O157 infection.

People who are infected can usually be cared for at home, and most will get better without medical treatment.

It's important to drink plenty of fluids, as diarrhoea can lead to dehydration.

You should contact your doctor as soon as possible if you or your child has bloody diarrhoea.

Antibiotics aren't recommended, and may increase the risk of complications.

Anti-diarrhoea drugs such as loperamide (Imodium) are also not recommended as they may prolong your exposure to the toxin.

Find out more about

caring for a child with gastroenteritis
caring for an adult with gastroenteritis

Prevent E. coli spreading

Very few E. coli bacteria are needed to cause illness, which makes E. coli very infectious.

Everyone should wash their hands regularly and thoroughly to prevent spreading E. coli at home.

Hand washing routine

It's important to wash your hands:

  • after contact with animals
  • after contact with an infected person, particularly after handling their clothes or bedding
  • after going to the toilet or changing babies' nappies
  • before preparing or serving food, or eating meals
  • after handling soiled bedclothes or clothing
  • after cleaning, even if you used protective gloves

Find out how to wash your hands properly.

Anyone who has been infected should avoid cooking or preparing food until 48 hours after their symptoms have cleared up.

Don't share towels or nappy changing mats.

Household cleaning advice

  • Wash infected clothing and bed linen separately from other clothes in a washing machine at the highest temperature possible, such as 60C.
  • Wipe down the outside of the washing machine with hot water and detergent after any heavily soiled load.
  • Clean toilet seats, toilet flush handles, basin taps, surfaces, and toilet door handles at least daily – if not more – using hot water and detergent.
  • Dispose of cloths by placing them in a plastic bag, sealing the neck, and placing them in the household waste.
  • Don't clean soiled items in the kitchen.
  • Clean any spillage of poo immediately. Use hot water and detergent, and wear heavy-duty domestic rubber gloves.
  • Thoroughly wash rubber gloves in hot water and detergent after use, then rinse and allow to dry.


Disinfectant sprays and wipes or alcohol-based wipes may be used on toilet seats and other surfaces, but only after any visible dirt has been removed.

Thick household bleach is highly effective.

  • Dilute one part bleach to every 10 parts water for soiled surfaces.
  • Dilute one part bleach to every 100 parts water for other hard surfaces.

Ideally, use heavy-duty domestic rubber gloves and disposable cloths for cleaning.

Returning to work or school

You should stay away from work or school until you've been completely free from symptoms for 48 hours.

Most people are no longer infectious after about a week.

Some people, particularly children, may carry the E. coli bacteria for several months after getting better.

You should take special care before returning to work or school if:

  • you work in health or social care – speak to your employer
  • your work involves handling food – speak to your employer
  • you have a child under five years of age – contact your doctor

This advice applies to people who've been infected and those who live in the same household.

Children aged under five recovering from an E. coli infection should avoid public swimming pools until test results give them the all clear.

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.