Sludge Watch ==> Where Ecoli O157 comes from and how it kills

[Maureen Reilly]

Where E. coli comes from and how it kills


The E. coli bacteria occurs naturally in the guts of most warm-blooded 
animals. All humans carry the common forms of E. coli in their intestines. 
It's essential for the healthy functioning of digestive systems, helping 
humans synthesize vitamins and suppress the growth of harmful bacteria.
But not all forms are so helpful. E. coli O157:H7, which was first 
identified in 1982, is a particularly nasty version. It secretes a powerful 
poison, called a verotoxin, that binds to receptors on human kidney, brain 
and gut cells and kills them.

Not all people have the receptors, which explains why some people — and 
animals, including cattle — who get O157:H7 become very ill and some 
don't.

E. coli O157:H7 is generally transmitted via infected fecal matter that has 
contaminated soil, water, fertilizer or, in the case of tainted meat, 
hamburger.

The danger to those infected with O157:H7 is that they will get a kind of 
kidney failure called hemolytic uremic syndrome, or HUS. It hits the very 
young and the very old the hardest.

People severely stricken with O157:H7 say it feels like a million tiny 
knives going through the body. Within days of symptom onset, what began as 
diarrhea turns to blood as the intestines break down.

By Elizabeth Weise, USA TODAY


http://www.usatoday.com/money/industries/food/2007-09-20-spinach-side-where-how_N.htm