Raw Sprouts can be contaminated with E.coli a few ways. The sprout seed is grown in
soil outside, which can contain pathogens from manure and can become a carrier (Ross, 2011).
The warm humid atmosphere needed to grow sprouts is the ideal pathogen growing environment.
They essentially become an incubator. The bean sprouts are soaked around 70°F for eight
hours and transferred to metal tanks and continuously sprinkled with water (Stephens, 2018).
The nutrients, moisture, and heat generated from the germination process are ideal
conditions for the growth of bacteria. Sprouts are harvested attached to the seed. The seed is
where bacteria may thrive and live. Even in the cleaning process, the outside is rinsed, but the
internal of the seed may hold bacteria. Cooking or “kill step” for sprouts would kill the bacteria;
however, sprouts are typically eaten raw. They could be irradiated but no one wants to do that
(Ross, 2011).
Mishandling of sprouts during production, packing, or distribution has not been
implicated as the main source of sprout contamination (Penn State, 2005). However,
bacteria already present can continue to thrive when proper food safety handling techniques
are not practiced during processing and preparation. If the bacteria, E. coli, is present, it
will continue to grow with the sprouts and even a cold-water wash step may not stop it
(Ross, 2011). E. coli once present can be hard to get rid of. The gentle handling, cleaning and
packing of sprouts is the right environment for E. coli, if present, to flourish and lead to
foodborne illness (CDC2, 2021).
What characteristics of, and processes involved with leafy greens allow leafy greens to be
contaminated with E.coli during growing, harvest and processing?
Similar to sprouts, leafy greens are grown in soil which causes its own issues. The
growing of leafy greens requires lots of water. Water is a source of contamination that can
come from the surrounding farm or adjacent lands. "You can get contamination from animal
production facilities, it gets into the sediment, it gets into the water, which gets irrigated onto the
crops, which are then harvested within 40 to 80 days," says Keith Warriner, a microbiologist
specializing in food safety at the University of Guelph, (CBC News, 2018). Another source of
contamination are birds flying over and animals walking through the fields of crops.
Leafy greens are typically harvested whole and packaged or sent for processing. This can
happen at the farm level or in a production facility. The transferring and handling of the delicate
leaves can cause contamination. Once contaminated, removing the bacteria is not easy. Washing
to remove the dirt from leaves can actually spread the contamination around more. During
processing, when the leaves are cut, sugars are released that bacteria like and can cause them to
grow even faster. Once in the facility it can spread and contaminate areas.
What characteristics of, and processes involved with ground beef allows the product to
be contaminated with E.coli during slaughter and processing?
E.coli is naturally occurring in the intestines of animals. The bacteria does not make the
animals sick, however Shiga toxin-producing E. coli, (STEC) is the bacteria that will make you
sick if ingested (Larsen, 2019). If an animal has STEC it can be transferred through their
excrements and then can get onto their feet, coat or the environment. The pathogens will be
transferred and continue with the animal through slaughter and then transferred to the meat. If
packed by hand, the handler may be moving the pathogen around to utensils, other packages, and
onto other products. The meat is now contaminated and when grounded up, the pathogen is
mixed all through the product. Since ground beef is raw, there is no heat step to eliminate the
pathogen prior to packaging. However, ground beef is not meant to be eaten raw and should be
cooked to an internal temperature of 165F (Tyko, 2019). Anyone handling raw ground beef
should follow food safety guidelines and wash hands, surfaces, and utensils with hot soapy water
to prevent contamination.
What are the necessary controls and prevention methods applicable in these two
industries?
Prevention starts where the produce and animals are grown and harvested. Most produce
and animals are contaminated by soil, fertilizers, animals, air, and water (FDA, 2021). Run offs
of water from contaminated sources feed into farms and contaminate animals and produce.
Knowing the areas around the harvest and monitoring water and soil sources for E.coli is one
way prevent contamination. The Produce Safety Rule established by the FDA and the Food
Safety Modernization Act (FSMA) set standards for scientifically limiting pathogen
contamination. Good Agricultural Practices (GAPs) help with limiting and preventing
contamination for both produce and animal raising. Having controls in place for proper hygiene
while harvesting is one way to address food safety and prevent transfer contamination.
Once the product, produce or animal, is sent for processing, there is still the possibility of
transfer of the pathogen to the processing environment. While it has been said that STEC E.coli
cannot produce biofilms, it has not been proven (Kornacki, 2020). So, eliminating this as a
potential source might just be turning the investigation in the wrong direction. The practice of
proper cleaning and sanitation is a good way to control and prevent re-contamination.
Generic E. coli is likely to be found in raw ready-to-eat products therefore pathogen
environmental testing plans should be developed. The FDA has created the Bacteriological
Analytical Manual to use in screening for pathogenic strains. Having plans in place to test for
critical pathogens will only help prevent the spread of the bacteria. The FDA also recommends
taking necessary steps at home to prevent the spread and contamination of E. Coli. Consumer
education is acritical step that most processors may not think about. The FDA suggests washing
your hands and utensils before use, rinsing all raw products with water, separating raw from
cooked foods, and using separate plates (CDC1, 2020). Overall, both the producers and
consumers need to be aware of the risks with raw products and take responsibility for preventing
contamination.
What is the Leafy Greens STEC Action Plan? Summarize its goals and plan of action.
The Leafy Greens STEC Action plan (LGAP) is a program developed by the U.S. Food
and Drug Administration (FDA) to improve the food safety of fresh leafy greens (FDA, 2021).
Due to the large number of Shiga toxin-producing E. coli (STEC) outbreaks associated with
leafy greens, the FDA decided they needed to act to prevent more outbreaks. Their goal was to
foster a relationship with the responsible stakeholders and create a more urgent, collaborative
approach to the food safety of leafy greens. This “One Health” approach was to help ensure
many stakeholders shared responsibility of the safety of the leafy greens.
Since the start of LGAP, the FDA has made significant progress by enhancing prevention
strategies, improving response activities, and identifying and addressing the knowledge gaps that
exist around STEC contamination of leafy greens. The LGAP focuses on those three main
priorities. Over the past few years, they have developed a list of eighteen action items stemming
from those three priorities. The prevention items address advance agricultural water safety,
enhance inspections, audit, and certification programs, buyer specifications, leafy greens data
trust, microbiological surveys for STEC detection, increase awareness and concerns for adjacent
lands, and establish regular outreach communication programs for stakeholders. Gathering data
at the source and inspections of the lands will help determine the sources of contamination.
Knowing where to start the investigations will improve on identifying the source.
The next step would be to respond to the incident. The response activities include
investigation reports, follow up surveillance, promote tech enabled traceability, improved
utilization of shopper data card, whole genome sequencing data submissions by states, advanced
root cause analysis, and improve outbreak and recall communications. Building credible
databases, utilizing science-based technology to trace, and tying it all together with a robust
recall system will improve response times and reactions. While outbreaks may never be
eliminated, these processes may help reduce the amount of people sicken during an outbreak.
Once the investigation is complete, a review of the process is needed. The final step in
the LGAP is addressing the knowledge gaps. This includes longitudinal studies, data mining,
analytics on previous outbreaks, adjacent nearby land usage, and compost sampling assignment
with California. The knowledge gaps are all about continuing to learn and better the processes
being used, and even create new ones with what is learned and discovered.
The FDA has so far completed over twenty-five action items from the LGAP. These are
not just accomplishments but learning experiences that continue to grow and expand with
additional tasks. The list of eighteen has grown to over forty-five items, showing they are adding
items as they learn about new ideas and causes. The FDA’s plan of action is to continue to work
on items and complete the list in the LGAP. The main goal is to limit the number of outbreaks
with this plan. Also, educating all stakeholders and making them aware and share in the
responsibility of food safety and GAPs. While the list may never be “done”, the key items being
accomplished are serving a purpose of providing additional training, improving processes and
identifying gaps.
References
CBC News. (2018). Here’s why lettuce keeps getting contaminated with E. coli. The Canadian
Broadcasting Corporation (CBC).
CDC1, Centers for Disease Control and Prevention. Outbreak of E. coli Infections Linked to
Romaine Lettuce, January 15, 2020. https://www.cdc.gov/ecoli/2019/o157h7-11-
19/index.html
CDC2, Centers for Disease Control and Prevention. Outbreak of E.coli Infections Linked to
Clover Sprouts, April 22, 2020. https://www.cdc.gov/ecoli/2020/o103h2-02-
20/index.html
FDA – U.S. Food & Drug Administration, April 6, 2021. Leafy Greens STEC Action Plan.
Leafy Greens STEC Action Plan | FDA
Kornacki, Jeffrey L. Ph.D. (August 17 th , 2020). Challenging Common STEC Assumptions. Food
Safety Magazine. https://www.food-safety.com/articles/6747-challenging-common-stec-
assumptions
Larsen, Linda. (April 2, 2019). How is ground Beef Contaminated with E.coli Bacteria?
Penn State Extension. (March 1, 2005). College of Agricultural Sciences Research and
Cooperative Extension. What You Should Know About Sprouts.
https://extension.psu.edu/what-you-should-know-about-sprouts
Ross Anderson. (2011, June 6). Sprouts and Bacteria: It’s the Growing Conditions. Food Safety
News (USA).
Stephens, M. James, (OCT 28, 2018). Bean Sprouts -Phaseolous Aureus R. And Glycine Max
(L.) Merr. UF IFAS Extension University of Florida.
https://edis.ifas.ufl.edu/publication/MV024
Tyko, Kelly. (June 20, 2019). USA Today. E.coli Ground Beef Outbreak ‘appears to be over’
after sickening 209 people in 10 states.
https://www.usatoday.com/story/money/food/2019/06/20/e-coli-outbreak-over-209-
people-were-sick-tainted-ground-beef/1513317001/