Cover Image: August 2011 Scientific American Magazine See Inside

E. coli on the March

Toxic strains of a common gut microbe are multiplying















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Image: Corbis

If the full name of any germ could be a household word, it would be Escherichia coli O157:H7, a bacterium that has in the past caused severe food poisoning linked to Jack in the Box hamburgers, Taco Bell lettuce and prepackaged spinach. Now E. coli O157:H7 is being overshadowed by more virulent strains of what is normally a benign gut microbe. This spring a recently identified strain of E. coli, O104:H4, killed dozens of people in Europe and landed hundreds more in the hospital. The U.S. Centers for Disease Control and Prevention is now following at least six types of so-called Shiga toxin E. coli, which, like O104:H4 and O157:H7, cause bloody diarrhea and, in extreme cases, fatal kidney failure. Below are some surprising facts you may have missed in this spring’s headlines.

  1. Antibiotics can worsen an E. coli infection. Giving antibiotics, including fluoroquinolones such as Cipro, can kill a patient who has been sickened by any strain of Shiga toxin E. coli. The reason: when the bacteria die, they release the toxin in massive amounts. Fortunately, one particular group of drugs, called carbapenems, seems to not trigger a major toxin release, but these drugs are generally prescribed only in special circumstances. This explains why travelers who bring antibiotics with them as a precautionary measure should not take them if they develop bloody diarrhea.
  2. E. coli O104:H4 is resistant to at least 14 antibiotics. Why this is so remains a mystery, particularly because many of these drugs are not usually used to treat E. coli infections. Somewhere along the line, either these bacteria or other bacteria with which they exchanged genetic material must have developed in an environment that was awash in antibiotics—possibly a hospital or a farm. 
  3. E. coli O104:H4 may eventually show up in the U.S. The CDC has already confirmed a few cases in U.S. residents who had recently traveled to Germany. Whereas health officials do not believe the current outbreak will spread in the U.S., a similar strain of E. coli could evolve here independently at some point.
  4. E. coli O157:H7 is becoming less of a threat. That is because the government has made it mandatory for food producers to report its presence to health authorities. But the number of ailments caused by the other Shiga toxin E. coli strains is growing rapidly. Many food-safety specialists believe that requiring food producers to report more E. coli strains to the government would help reduce the incidence of illness.



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  1. 1. eddiequest 09:22 AM 8/7/11

    2 words - COLLOIDAL SILVER

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  2. 2. ironjustice 04:52 PM 8/7/11

    "Giving antibiotics, including fluoroquinolones such as Cipro, can kill a patient who has been sickened by any strain of Shiga toxin E. coli."

    So what this basically says is they USUALLY use an iron binding drug / cipro to attack E. coli and therefore one might think the addition of iron to all our foods would be a bad thing because it would allow for an overgrowth / proliferation of the E. coli ? Logic and reason.

    "Ciprofloxacin: a novel therapeutic agent for iron overload?"
    "Many bacteria depend on iron for their growth;examples are Escherichia coli; Klebsiella, Pseudomonas, Salmonella,Yersinia, Listeria, and Staphylococcus species; and Haemophilus influenzae."

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  3. 3. sunnystrobe 04:23 AM 8/8/11

    E Coli is evolution writ large staring us in the face!
    What no press release seems to have highlighted, is the fact that the commercially driven chronic overuse of antibiotics fed to mass-reared animals has brought about this problem in the first place.
    If we switched to a plant-based nutrition youthevity.com, we would have far less health problems;
    let's not shoot the messenger, and blame the sprouts; it's our own dirty habits of not washing our hands after contact with fecal matter,
    from whatever provenance, from our own, or the hardly-ever-filmed slaughterhouses; see FOOD INC. for that matter.

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  4. 4. ironjustice 12:56 AM 8/9/11

    It seems simple root of the word 'Scientific' does not actually mean science in this journal. It is going the way of Fark. My comment as to the WHERE might there BE reservoirs of bacteria which contribute to bacteria in our food chain has been removed.
    "Reduced hygiene and use of crystal methamphetamine were
    associated with acquisition of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA)"

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  5. 5. JacobSilver 08:44 AM 8/10/11

    We are running out of actions to save ourselves. The origin of pathological e-coli (157:H7) was the irresponsible practice of feeding corn to antelope member animals, cattle, in large feedlots. To survive, and many of the calves first fed corn do not, the cattle had to develop e-coli (157:H7) to process the the grain digestively by acid, instead of the normal fermentation process they use for grass. E-coli (157:H7) does not break down in human stomach acid; hence, it is toxic. And now, e-coli (157:H7), which can persist in the external atmosphere, usually in the manure of feed-lot cattle, has not exchanged genetic material with other bacteria and has become a more generic pathology, e-coli (104:H4). And you cannot avoid this pathological bacterium by only eating organic food. The idiots who organized the American factory farms have now brought disaster to potentially all of us. Let's hear it for the factory farms and the chemical industry!

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  6. 6. jgrosay 11:48 AM 8/10/11

    It seems that the extremely noxious features of some E coli strains is due to a bacteriophage virus that induce them to produce and release Shiga toxin. If you give an antibiotic that kills rods, they release toxin while dying and the pateint worsens. The ability of E coli strains to produce Verocytotoxin is highly variable, and so is the effect of antibiotics on the production and release of toxin. From a theoretical point of view, bacteriostatic drugs should reduce the production of toxin by slowing the bacterial metabolism, but this must be tested in an individual case basis, thru the adequate lab tests. From a general point of view, it can be said that drugs that act by slowing gut mobility, for example Loperamide, are very bad in cases of toxigenic E coli infections, as they increase the possibility that the body absorbs and is damaged by the verocytotoxin. Besides this, actions must be taken on an individual basis, please consult your doctor. Early start of intravenous fluid therapy seems being of help. Do you suffer bloody diarrhea ? --> Go the hospital emergency room.

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