E. coli O157:H7

E. coli O157:H7 is a strain of E. coli (Escherichia coli) that has been linked to a number of major food safety outbreaks since the late 20th century. This strain is enterohemorrhagic; that is, it produces Shiga toxins that cause hemorrhaging and a life-threatening kidney condition called hemolytic uremic syndrome (HUS).

Causes of Infection and Outbreaks
Because E. coli lives in feces, infections and outbreaks of E. coli O157:H7 are inevitably related to exposure to feces. A common vector of contamination is cattle manure, which either contaminates beef (often ground beef) in slaughterhouses, or contaminates vegetables via runoff. Human feces can also pose a risk, via people who do not wash their hands after using the toilet. According to the Mayo Clinic:ref>E. coli Causes, Mayo Clinic, Accessed June 19, 2011.


 * "Human and animal feces may pollute ground and surface water, including streams, rivers, lakes and water used to irrigate crops. Drinking or inadvertently swallowing untreated water from lakes and streams can cause E. coli infection.


 * "Although public water systems use chlorine, ultraviolet light or ozone to kill E. coli, some outbreaks have been linked to contaminated municipal water supplies. Private wells are a greater cause for concern. Some people have been infected after swimming in pools or lakes contaminated with feces."

Some speculate that use of sewage sludge as fertilizer may represent a risk of E. coli exposure.

Symptoms
Patients typically begin developing symptoms of severe abdominal cramps, bloody diarrhea, and sometimes nausea or vomiting three to four days after ingesting food tainted with E. coli O157:H7, but some develop symptoms as soon as one day after exposure or up to a week after exposure. One patient described the experience as follows:


 * "Two days [after eating a tainted spinach salad], I started feeling sick. It was a Friday and I was at work. I thought it was no big deal - probably something I ate - and wondered if I should go home and decided to stay at work, but then began feeling a lot worse.


 * "That Saturday night - I'm a professional vocalist and I had two gigs, one right after the other. I had a retirement party that was a really fancy, elegant sort of event and we were the entertainment for that - we were a trio -, they had a beautiful dinner with everything, and I couldn't eat anything. Everything I ate was making me sick so I asked the person for an herbal tea, tried to get that down, and then I went to another gig that started at 9pm and went until 1am.


 * "I kept feeling lousy, and then the next morning I had to get up early and get to the children's choir that I did at the time at a church. I remember sitting there thinking, "I can hardly stand up. I don't know what's wrong with me." When you haven't eaten for a few days, you feel lousy, but this was something else.


 * "So I went home and I had a lot of cramps, a lot of bloating, a lot of diarrhea, and I was really nauseous, and I went to bed... I stayed in bed all day Sunday, I went to work Monday and left work early. Tuesday, Wednesday I stayed in bed... I was progressively getting more and more sick and because I wasn't eating, there wasn't a whole lot to go through me at that point. I was drinking water until probably Tuesday or Wednesday and then I couldn't even drink water, I had such bad cramps.


 * "And then it turned bloody. And I thought for sure I was hemorrhaging and I was dying of something and I had no idea what. I wasn't sleeping much...the cramps reminded me of labor cramps because it was on a certain schedule and you knew they were coming. It would be really bad cramps and then I'd have to run to the bathroom and it would be blood. The word for that was "unrelenting." And it was every hour, and then it was every half hour, and then it became every ten, fifteen minutes."

Long Term Health Problems
After suffering from E. coli O157:H7, patients often experience lifelong health problems. One patient described her problems as follows:


 * "What I was told when I was discharged [from the hospital] was no caffeine, no alcohol, and I couldn't eat anything raw, I could only eat cooked food. So I have been struggling for almost four years now with my digestion because there's not a cure or a treatment. I went back to the doctor and had a number of tests done because I swell up like a balloon at times, which I was told was kidney problems, and I still had a hard time staying hydrated. But given their parameters they said there was no kidney failure, there was perhaps kidney damage. I was also having a hard time walking with severe pain in my hip and it was determined by a chiropractor that my soaz muscle, which had cramped up so much from the infection, was pulling my hip out of its socket.


 * "I have diarrhea every day. It's been that way since. And what the doctor said is that I probably had irritable bowel syndrome, but I really don't think that that's the case because irritable bowel is constipation and then diarrhea and then constipation and then diarrhea, and I just always have diarrhea.


 * "So I went, finally, to an Ayurvedic doctor and she said, "You were just born and got sick in the wrong country. If you were in France, they would have put you on this clay right away. And I asked, "What kind of clay is that?" And she said it's three kinds actually, and they mix it together", and basically, you're eating dirt. But it's the only thing that has helped me. It's the only thing that has made my digestion not constant diarrhea so that I could at least get some nutrition from my food. Kaolin clay, diatomaceous earth, and bentonite clay. So the three of those together helps."

Related Sourcewatch articles

 * E. coli
 * E. coli O104:H4
 * Sewage sludge

External Resources

 * E. coli, Centers for Disease Control

External Articles

 * Jill Richardson, Food Poisoning Diaries: E. Coli, La Vida Locavore, July 12, 2010.