What is E. coli?

Escherichia coli (E. coli) are bacteria that live in human and animal intestines. Shiga toxin-producing strains of E. coli, or STECs, are responsible for most food-related E. coli infections. In 2011 the Centers for Disease Control and Prevention estimated that E. coli infections account for over 2,000 hospitalizations in the United States each year.

Pathogenic E. coli is most commonly found in cows, although chickens, deer, sheep, and pigs have also been known to carry it. Meat becomes contaminated during slaughter, when infected animal intestines or feces come in contact with the carcass. Ground or mechanically tenderized meats are considered riskier than intact cuts of meat because E. coli bacteria, can be mixed throughout the meat in the grinding process or during tenderization.

Other foods that sometimes become contaminated with E. coli bacteria include unpasteurized milk and cheese, unpasteurized juices, alfalfa and radish sprouts, lettuce, spinach, and water. However, any food is at risk of becoming contaminated with E. coli through cross-contamination. One can also get E. coli bacteria from contact with feces of infected animals or people.

What characterizes the illness caused by E. coli?

E. coli symptoms change as the infection progresses. Symptoms usually begin two to five days after infection. The initial symptoms include the sudden onset of cramps and abdominal pain, followed by diarrhea within 24 hours. Diarrhea will become increasingly watery, and then noticeably bloody. People with E. coli infection also often feel nauseated and experience headaches. Less common symptoms include fever and chills.

Hemolytic Uremic Syndrome, or HUS, is a rare but serious complication of E. coli infection. HUS occurs when Shiga toxin gets into the bloodstream and causes the part of the kidney that filters toxins out of the blood to break down, causing kidney injury and sometimes failure.  Some HUS patients also suffer damage to the pancreas and central nervous system impairment.

You can learn more about E. coli infection at Foodborneillness.com.