You’ve heard of E. coli. It’s that bacteria that pops up in the headlines once in a while because of its association with serious illness and massive recalls. But is that the whole story? What IS E. coli, exactly? How do scientists use E. coli? How does it get into your food? And how can you protect yourself from getting sick because of E. coli?

Well, E. coli stands for Escherichia coli, a bacteria named after its discoverer, Theodore Escherich. It is a commensal organism of warm-blooded animals - it lives in the digestive systems of mammals.

Yes, this means E. coli is a normal inhabitant of humans!

I’ve tested myself for E. coli, and found it - and if I were to test you for E. coli, there’s a good chance it’ll be there, too! But then, you might ask, if there’s E. coli in me, why am I not sick right now?

Well, let’s put it this way - humans belong to one species (Homo sapiens). And yet, humans are not all the same. Some of us are more laid-back, some of us love roller coasters, some of us love stinky goat cheese, and some of us are just plain dangerous.

This is how it is for E. coli as well. Some types, or strains, of E. coli can live in humans without harming them at all. Obviously, the ones that live in our bodies without causing disease are harmless - to us, anyway.

Others can be very dangerous, like E. coli O157: H7, which causes a particularly serious illness that’s accompanied by bloody diarrhea and may cause kidney failure. This is why E. coli O157: H7 is considered so dangerous. Young children and the elderly are particularly vulnerable.

So, a small number of E. coli strains have to potential to make people sick, but the majority of them are harmless.

Scientists use both disease-causing (pathogenic) and non-disease causing (non-pathogenic) strains in their research.

The next part of this series will focus on how E. coli is useful and how E. coli gets into your food.

You can also find this article at my Squidoo page: E. coli at Squidoo.