Understanding E. coli

HEALTH news has been dominated over the last couple of weeks by coverage of the devastating German outbreak of E. coli food poisoning. At the time of writing, the cause of the outbreak is still uncertain with thousands of people ill and over 25 dead. However, the number of new cases appears to be dropping which hopefully means that the crisis is starting to abate. It’s still important to be aware of the facts...

What is E. coli?

E. coli (the 'E' stands for 'Escherichia') is the family name for a group of bacteria. Within this family, there are thousands of different strains, most of which are harmless (as a comparison, both Vinnie Jones and I share the family name Jones, but we are very different creatures!). In fact some strains are positively beneficial and at least one is used as a probiotic supplement in some countries. 

E. coli thrives at body temperature and is found in the large intestines of warm-blooded animals, including humans. In fact it starts to colonise our guts from the moment we are born, so it is entirely normal for us to be carrying E. coli.

However, a small number of members of this family group are associated with severe food poisoning, which can result in kidney failure and death. As well as the current outbreak in Germany, there have been recent outbreaks in the USA (2006) and Scotland (1996). The different strains of E. coli associated with illness are usually identified by a number, e.g. O104-H4 in the German case. Large numbers of E. coli are excreted in the faeces of both animals and humans and outbreaks of illness attributed to strains of E. coli are linked to faecal contamination of food (eg. by food handlers not washing their hands properly after going to the loo or animal manure getting onto the food somehow).

Where has this toxic strain of E. coli come from?

 Of course, as I write this, the cause is still unknown. The spotlight has been on Spanish cucumbers (the suggestion being that the crops had been fertilised with animal manure) and on German bean sprouts (grown in warm, moist conditions that are very favourable for bacterial growth).

Tests on both of these have been negative, which may be because neither is the source of the problem or the contamination is no longer active. Note that the German authorities, although criticised for making public too quickly suspected sources of the outbreak, are caught between trying to do a very difficult detective job and containing the crisis by keeping the public informed.

Should I be worried?

In the words of another family member (Corporal Jones of Dads' Army), "Don't panic!” The outbreak appears to be contained to Germany or visitors to Germany and there is no reason to suppose that the current infection will spread. However, this health crisis has highlighted a number of areas of concern for the future:

• The increasing globalisation of food production means that it is much harder to keep tabs on where a problem like this one has originated. This means that we may see other large outbreaks like this one in the future.
• The on-going demand for cheap food may encourage some food producers to cut corners, especially as far as food safety is concerned, which means that there is an increased risk of such outbreaks.
• Routine use of antibiotics, such as in cattle, has encouraged the development of bacterial strains that are resistant to antibiotics, making toxic strains harder to contain.

How can I find out more?

There are several excellent sources of information both on the current E. coli O104-H4 outbreak and on food handling and preparation:

• For official updates and advice, check out the Food Standards Agency website (www.food.gov.uk).

• If you are travelling to Germany, check out the Health Protection Agency website (www.hpa.org.uk)
• If you have recently returned from Germany and have symptoms of food poisoning, including bloody diarrhoea, get medical advice.

And finally... don't blame the cucumbers!

So far, the potential sources of bacterial contamination in the current outbreak have all been salad vegetables but this doesn't mean that we should stop eating vegetables.

Eating fruit and vegetables continues to be a healthy option as long as we take the normal precautions of washing and preparing them properly and remembering personal hygiene when preparing and handling food. Remember, it's not the fruit and vegetables that are the problem.

The advice given here is not intended to replace medical advice. Always consult your GP if you are concerned about your health.