Why is the E. coli O157:H7 bacterium of special concern in ground beef?
E. coli O157:H7 can colonize in the intestines of animals, which could contaminate muscle meat at slaughter. O157:H7 is a strain of E. coli that produces large quantities of a potent toxin that forms in the intestine and causes severe damage to the lining of the intestine. The disease produced by the bacteria is called Hemorrhagic Colitis. E. coli O157:H7 survive refrigerator and freezer temperatures. Once they get in food, they can multiply very slowly at temperatures as low as 44 °F. The actual infectious dose is unknown, but most scientists believe it takes only a small number of this strain of E. coli to cause serious illness and even death, especially in children. It is killed by thorough cooking. Illnesses caused by E. coli O157:H7 have been linked with the consumption of undercooked ground beef. Raw milk, apple cider, dry cured sausage, and undercooked roast beef have also been implicated.
