Escherichia coli (or E. coli) is the most prevalent infecting organism in the family of gram-negative bacteria known as enterobacteriaceae. More than 700 serotypes of E. coli have been identified. The E. coli that are responsible for the numerous reports of contaminated foods and beverages are those that produce Shiga toxin, so called because the toxin is virtually identical to that produced by Shigella dysenteria type . The best-known and also most notorious E. coli bacteria that produce Shiga toxin is E. coli O157:H7
Six pathotypes are associated with diarrhea and collectively are referred to as diarrheagenic E. coli.
- Shiga toxin-producing coli(STEC)—STEC may also be referred to as Verocytotoxin-producing E. coli (VTEC) or enterohemorrhagic E. coli (EHEC). This type is the one most commonly heard about in the news in association with foodborne outbreaks.
- Enterotoxigenic E. coli(ETEC)
- Enteropathogenic E. coli(EPEC)
- Enteroaggregative E. coli(EAEC)
- Enteroinvasive E. coli(EIEC)
- Diffusely adherent coli(DAEC)
The testing done to distinguish E. coli O157:H7 from its other E. coli counterparts is called serotyping.
Although foods of bovine origin are the most common cause of both outbreaks and sporadic cases of E. coli O157:H7 infections, outbreaks of illnesses have been linked to a wide variety of food items. Outbreaks have been linked to alfalfa, clover and radish sprouts, lettuce, and spinach. Other vehicles for outbreaks include unpasteurized juices, yogurt, dried salami, mayonnaise, raw milk, game meats, hazelnuts, and raw cookie dough.
One severe complication associated with E. coli infection is hemolytic uremic syndrome (HUS). The infection produces toxic substances that destroy red blood cells, causing kidney injury. HUS can require intensive care, kidney dialysis, and transfusions
Signs and symptoms of E. coli O157:H7 infection typically begin three or four days after exposure to the bacteria, though you may become ill as soon as one day after to more than a week later.
Symptoms
- Diarrhea, which may range from mild and watery to severe and bloody
- Abdominal cramping, pain or tenderness
- Nausea and vomiting
- Symptoms of HUS include decreased urine production, dark or tea-colored urine, and facial pallor
Prevention
- Wash hands thoroughly after using the bathroom or changing diapers and before preparing or eating food, after contact with animals or their environments (at farms, petting zoos, fairs, even your own backyard).
- Cook meats thoroughly.
- Avoid raw milk, unpasteurized dairy products, and unpasteurized juices (like fresh apple cider).
- Do not swallowing water when swimming or playing in lakes, ponds, streams, swimming pools, and backyard “kiddie” pools.
- Prevent cross contamination in food preparation areas by thoroughly washing hands, counters, cutting boards, and utensils after they touch raw meat.
STEC infections are usually diagnosed through laboratory testing of stool specimens. Identifying the specific strain of STEC is essential for public health purposes, such as finding outbreaks. Many labs can determine if STEC are present, and most can identify E. coli O157. Labs that test for the presence of Shiga toxins in stool can detect non-O157 STEC infections
Test options
E Coli: Direct detection of E. coli O157
A.I.I Panel : Acute intestinal Infections Panel
Learn more about E coli
http://www.foodsafety.gov/poisoning/causes/bacteriaviruses/ecoli/
http://www.mayoclinic.org/diseases-conditions/e-coli/basics/definition/con-20032105
