Q&A: E.Coli

What is E.coli?:E.coli is short for Escherichia coli, a type of bacterium present in the gut of humans and animals. It is a common bacterium with many subtypes. Some never cause harm, a small number cause serious illness. E.coli 0157, found in contaminated meat, can cause a similar syndrome to E.coli 0104, which has been identified as the cause of the current outbreak. The exact source of the microbe in Germany remains a mystery.

Is this a new strain?

Some experts have said the type of E.coli identified in this outbreak is a new variant, but the European Centre for Disease Prevention and Control says that “serotype STEC 0104 has caused food-borne outbreaks of diarrhoea and haemolytic uraemic syndrome, or isolated cases, before”.

An outbreak was documented in Montana in 1994 and a single case in the Far East in 2006. The H4 variant of E.coli 0104 was identified as the cause in the 2006 case.

What symptoms does it cause?

The severity of illness varies but some types of E.coli cause severe stomach cramps and bloody diarrhoea. Anyone returning from Germany with these symptoms should seek medical advice.

Why do so many people need hospital treatment?

Haemolytic uraemic syndrome, the specific illness that has caused at least 18 deaths and led to hundreds of people requiring treatment in intensive care, is a serious complication of infection with a certain type of E.coli.

Haemolytic refers to the destruction of red blood cells by a toxin produced by the bug and to a drop in platelets. Uraemic refers to high levels of urea found in the blood as the kidneys fail. A poisonous toxin, the Shiga toxin, is produced by some types of E.coli, which can cause the kidneys to fail and may lead to blood disorders.

What age group is most at risk?

The outbreak is most prevalent in young and middle-aged women.

What precautions can help minimise the risk of infection? Travellers to Germany should avoid eating raw tomatoes, cucumbers and lettuce. It is thought cattle manure, used as a fertiliser, is a likely culprit. People should thoroughly wash all fruit and vegetables. Peeling and cooking will remove bugs.

Some experts suggest contaminated irrigation water could colonise the roots of fruit and vegetables, allowing the bacterium to enter the inside of the product.

Can E.coli be transmitted from person to person?

If someone were to develop a mild form of gastroenteritis due to the microbe, it would be present in their faeces. Inadequate hand hygiene could lead to E.coli being transferred to food, putting those who eat contaminated food at risk.

How is the infection treated?

In milder cases, with fluids and painkillers. Those with a severe illness and complications may require intensive care in hospital, including dialysis and high-tech interventions. Doctors are divided as to the use of antibiotics because of drug resistance and a fear of aggravating the disease.