1. E. Coli contamination in produce: the rising concern for consumers
Jessica Strauch
Walden University
August 2, 2011
The purpose of this presentation is to educate the general public on the danger of E. coli in the produce supply and methods to prevent E. coli exposure. In recent years, E. coli, a bacteria primarily found in beef products, has been found in many different types of produce. Therefore, because of the illnesses associated with ingesting E. coli tainted foods, prevention at home will be an important step in keeping the population healthy.

2. Learning outcomes E. coli E. coli in Produce How to Avoid Illness
Basic Introduction
Illnesses that are caused
E. coli in Produce
How contamination occurs
Commonly affected foods
Recent outbreaks
How to Avoid Illness
This talk will aim to examine E. coli contamination in produce by first discussing what E. coli is, along with illnesses associated with toxic outbreaks. Second, this talk will focus specifically on E. coli contamination in produce; how contamination occurs, commonly affected foods, and discuss some of the more recent outbreaks of contamination. Finally, this talk will let the consumer know what can be done to avoid illness caused by E. coli contamination.

3. Introduction to e. coli
Let us start with a basic overview of what E. coli is. E. coli, short for Escherichia coli, is a strain of bacteria that live in the intestines of humans and animals. Most strains of E. coli are found to be harmless, even some of those strains found in our intestines are beneficial for proper digestion. However, certain strains of E. coli have been discovered that can cause illness as well. Two of the most toxic strains that have been found to cause illnesses are E. Coli O157:H7 and the newly discovered strain, E. Coli O104:H4. While E. coli contamination is not found only in food, it can also contaminate the water supply, about 85% of cases are associated with food contamination.
Bacteria found in intestines of humans and animals
Two toxic strains: E. Coli O157:H7 and E. Coli O104:H4

4. Illness caused by outbreaks
Estimated 73,000 cases of illness yearly
60 deaths
Common symptoms include:
Mild to severe diarrhea
Abdominal cramping
Blood in the stools
Severe symptoms include:
Kidney failure
Damaged red blood cells
Each year in the United States, there are an estimated 73,000 cases of sickness caused by all forms of E. coli that are reported, with E. coli O157:H7 being the most common, and also the most common cause of death. There are 60 deaths reported yearly due to E. coli contamination. The primary subgroups of the population that are affected by E. Coli contamination and thus develop greater illnesses are: children under 5, pregnant women, and the elderly. Common symptoms of E. coli contamination are gastrointestinal in general, including: mild to severe diarrhea, abdominal cramping, and bloody stools. There is usually no fever present with these other symptoms. In extreme cases of poisoning, generally in the subgroups at higher risk and occurring in 1 in 50 cases, hemolytic uremic syndrome occurs, leading to kidney failure and damage of the red blood cells. This is fatal if not treated promptly. All symptoms will usually develop within 3-4 days of eating the contaminated food, and a physician should be called promptly if E. coli infection is suspected.

5. e. Coli contamination of produce
So now that there is a better understanding of what E. coli is and the illness it can cause, let’s take a look at how the contamination of produce can occur. Toxic E. coli strains from contamination of the slaughtering of cattle can infect nearby cattle that are still growing. The E. coli can then spread to irrigation channels that feed nearby produce farms or can be spread through the use of manure as fertilizer. In both cases, the produce is subsequently contaminated with E. coli.

6. Produce commonly affected
Sprouts
Alfalfa
Bean
Lettuce
Spinach
While any produce is at risk for contamination from E. coli, the most common outbreaks seem to be in root crops and leafy vegetables. This includes, but is my no means limited to: sprouts of any variety (alfalfa, broccoli, bean), lettuce and spinach.

7. Outbreak – germany 2011 Caused by E. coli O104:H4
Due to contamination of raw bean sprouts
852 cases of hemolytic uremic syndrome
32 deaths
The most recent E. coli outbreak that has been seen was in Germany this year. It was found to have been caused by the new strain of E. coli, O104:H4. This is estimated to be the deadliest outbreak of E. coli seen to date. The cause of the outbreak was traced to one farm in Germany that grew raw bean sprouts. 852 cases of hemolytic uremic syndrome were attributed to this E. coli outbreak, along with 32 deaths.
Center for Disease Control. (2011). Investigation Update: Outbreak of Shiga toxin-producing E. coli O104 (STEC O104:H4) Infections Associated with Travel to Germany. Retrieved from:

8. Outbreak – united states 2010
Caused by E. coli O145
Due to contamination of shredded romaine lettuce
26 known cases; 7 probable
0 deaths
Previously in 2010, there was an outbreak of E. coli O145 that was reported in five states: Michigan, Ohio, New York, Pennsylvania, and Tennessee. This outbreak was traced to a single processing facility that processed romaine lettuce. There were 26 known reported cases due to the outbreak, with three reported cases of hemolytic uremic syndrome. Luckily with this outbreak, there were no deaths linked to the E. coli contamination.
Center for Disease Control. (2010). Investigation Update: Multistate Outbreak of Human E. coli O145 Infections Linked to Shredded Romaine Lettuce from a Single Processing Facility. Retrieved from:

9. Outbreak – united states 2006
Caused by E. coli O157:H7
Due to contamination of raw spinach
199 reported cases
3 deaths
In 2006, there was a large outbreak in the United States of raw spinach contamination of E. coli 157:H7. The outbreak affected individuals in 26 states, with 199 reported cases. The outbreak was linked to raw spinach from a single manufacturing facility. Of the 199 reported cases, 31 cases developed hemolytic uremic syndrome, and 3 deaths were linked to the outbreak: 2 elderly women and one child.
Center for Disease Control. (2006). Update on Multi-State Outbreak of E. coli O157:H7 Infections From Fresh Spinach, October 6, Retrieved from:

10. Prevention measures While grocery shopping: At home:
Purchase only the freshest looking produce
Check the smell
Keep meat and produce separate
At home:
Store in refrigerator promptly
Always keep covered
Wash before using
Throw away anything questionable
As was illustrated through the overview of recent outbreaks, both the strain of E. coli and the produce involved cannot be predicted. However, there are general measures that any person can take to avoid potential illness caused through an E. coli outbreak, as recommended by the Produce Marketing Association. While grocery shopping there are a few measures that can be taken, including: buying only fresh-looking fruits and vegetables; making sure that there are no strange odors on the produce; and keep meats and produce separated in the grocery cart. At home: store produce as soon as it is home, preferably in the crisper; if not in the crisper, ensure that all produce is covered tightly; always wash everything in clean water prior to using; and discard any produce that may have a questionable odor or is slimy to touch.

11. conclusions Toxic strains: E. coli O157:H7 and E. coli O104:H4
At risk populations: children, pregnant women, the elderly
Produce contamination caused by cattle farms
2011 outbreak in Germany deadliest in history
Consumer prevention relies on measures taken in the store and at home
Overall, E. coli are bacteria that comes in many strains, with some of the more toxic strains including E. coli O157:H7 and O104:H4. Generally, ingestion of contaminated food may lead to no or mild symptoms. However, in some cases, the symptoms can become severe, leading to hemolytic uremic syndrome, and in rare cases, death. Generally, the more serious cases are present in young children, pregnant women, and the elderly. The contamination of produce comes from either the use of manure from contaminated cattle or from water coming from runoff of those same type of cattle farms. E. coli contamination can occur in any type of fruit or vegetable, although the most common are root and leafy vegetables. Based on the recent outbreaks of the last 5 years, it can be seen that the strain of E. coli and the type of produce are very unpredictable. For proper prevention measures, careful choosing of fresh fruits and vegetables at the store along with the correct storage and cleansing of produce will help to keep E. coli ingestion to a minimum. If an outbreak of E. coli is reported, it will be vital to ensure proper handling of all produce and for the high risk populations to avoid the produce until the contamination source is found and dealt with.

12. references
Center for Disease Control. (2006a). Questions & answers: sickness caused by E. coli. Retrieved from: Center for Disease Control. (2006b). Update on Multi-State Outbreak of E. coli O157:H7 Infections From Fresh Spinach, October 6, Retrieved from: Center for Disease Control. (2010). Investigation Update: Multistate Outbreak of Human E. coli O145 Infections Linked to Shredded Romaine Lettuce from a Single Processing Facility. Retrieved from: Center for Disease Control. (2011). Investigation Update: Outbreak of Shiga toxin-producing E. coli O104 (STEC O104:H4) Infections Associated with Travel to Germany. Retrieved from:

13. references
Davis, J.G. & Kendall, P. (2005). Preventing E. coli from garden to plate. Retrieved from: Organic Trade Association. (2011). E. coli facts. Retrieved from: Scott, V.N. & Stevenson, K.E. (2006). HACCP: A Systematic Approach to Food Safety (4th ed.). Washington, D.C., Grocery Manufacturers Association. Washington State Department of Health. (2011). E. coli. Retrieved from:

14. Further reading For medical/biological information regarding E. coli:
Berg, H.C. (2004). E. coli in Motion. New York: Springer Press.
For information regarding E. coli and current worldwide outbreaks visit: Center for Disease Control. (2011). E. coli. Retrieved from:
For outbreaks and consumer resources:
Marler Clark. (2011). About E. coli. Retrieved from:
For further information on E. coli, current outbreaks, or scientific understanding of E. coli, please consult some of the above references.