Escherichia coli (E. coli)

E. coli are common germs (bacteria) normally found in the gut of warm-blooded animals and people. Some types of E. coli can cause vomiting or diarrhoea.


There are many types of E. coli, most of which are harmless and are an important part of a healthy gut. However, some types can cause illness.

One type of E. coli that causes illness is Shiga-toxin producing E. coli (STEC, sometimes also called Verotoxin-producing E. coli or VTEC)

People get sick from STEC from:

  • drinking contaminated water or eating contaminated raw food
  • drinking unpasteurised milk
  • contact with infected animals or faeces (poo) of infected people. 

It usually takes between 2–10 days after the bacteria are ingested for the first symptoms to appear.

Time off from kura or school

Children should stay away from kura or school until at least 48 hours after the diarrhoea has stopped.


The symptoms of STEC infection may include:

  • severe stomach cramps
  • mild to severe diarrhoea (which may be bloody)
  • vomiting
  • mild fever.

Most people recover within 5–7 days. Symptoms are generally mild in healthy people, however, they can be severe in children, the elderly, and people with reduced immunity.

E. coli can also cause a serious and potentially life-threatening complication known as haemolytic uremic syndrome (HUS) which affects the kidneys and bloodstream. Symptoms include:

  • dehydration
  • lethargy (exhaustion)
  • pale skin due to anaemia


Treatment for E. coli depends on how serious the illness is.  If you are not very sick, keep drinking lots of fluids.

If you have diarrhoea that is severe or has blood in it, or if you have a high fever with your diarrhoea, you should see your doctor.

Call Healthline 0800 611 116 if you are unsure what you should do.


You can reduce your chances of E. coli infection by practising good hygiene. 

  • Always wash your hands after going to the toilet or changing a nappy.
  • Avoid eating risky foods such as unpasteurised dairy products and unwashed raw fruit and vegetables
  • Always prepare, cook and store your food safely.
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