E. coli bacteria: what are they, where did they come from, and why are some so dangerous?
Escherichia coli (E. coli) are members of a large group of bacterial germs that inhabit the intestinal tract of humans and other warm blooded animals (mammals, birds). Newborns have a sterile alimentary tract which within two days becomes colonized with E. coli.
More than 700 serotypes of E. coli have been identified. The different E. coli serotypes are distinguished by their “O” and “H” antigens on their bodies and flagella, respectively. The E. coli serotypes that are responsible for the numerous reports of contaminated foods and beverages are those that produce Shiga toxin (Stx), so called because the toxin is virtually identical to that produced by another bacteria known as Shigella dysenteria type 1 (that also causes bloody diarrhea and hemolytic uremic syndrome [HUS] in emerging countries like Bangladesh) (Griffin & Tauxe, 1991, p. 60, 73).
The best known and most notorious Stx-producing E. coli is E. coli O157:H7. It is important to remember that most kinds of E. coli bacteria do not cause disease in humans, indeed, some are beneficial, and some cause infections other than gastrointestinal infections, such urinary tract infections. This section deals specifically with Stx-producing E. coli, including specifically E. coli O157:H7.
Shiga toxin is one of the most potent toxins known to man, so much so that the Centers for Disease Control and Prevention (CDC) lists it as a potential bioterrorist agent (CDC, n.d.). It seems likely that DNA from Shiga toxin-producing Shigella bacteria was transferred by a bacteriophage (a virus that infects bacteria) to otherwise harmless E. coli bacteria, thereby providing them with the genetic material to produce Shiga toxin.Continue Reading E. coli
Not exactly a big one, but still a Class I, High health risk recall of 1,560 pounds of beef cheek products because they may be contaminated with E. coli O157:H7 was announced late today by the U.S. Department of Agriculture’s Food Safety & Inspection Service (FSIS).
You cannot see it, taste it, or smell it. 250,000 E. coli O157:H7 (E. coli) bacteria will fit on the head of a pin. Ten to 50 will kill your child or your grandmother.
The recall now includes all beef trimmings and other products intended for use in raw ground beef processed between May 16 and June 26, 2008.