E. coli is a bacteria commonly found in the intestines of humans and animals. Most strains are harmless, but some can cause illness. The document discusses Shiga toxin-producing E. coli (STEC), the strain responsible for many foodborne outbreaks. It details two outbreaks of E. coli O26 infections linked to Chipotle restaurants in 2015. Symptoms of STEC infection include severe abdominal cramps, diarrhea (often bloody), and sometimes vomiting. Illnesses usually last 5-7 days but occasionally cause a severe complication called hemolytic uremic syndrome. Prevention strategies include thoroughly cooking ground beef and washing hands after contact with animals.

1. E.coli
Escherichia coli
Presented by Philip Danquah, MSW, ASW

2. E. coli
Foodborne Outbreak Please contact your local health department,
also known as a county or city health
department, if you believe you or someone
you know became ill from eating a certain
food. Ask to speak with the environmental
health specialist, or sanitarian, about a
possible food problem. Refer to your state
health department website to find more
information about how to contact your local
health department.
CDC (2017)

3. Escherichia coli
Bacteria found in the environment, foods,
and intestines of people and animals
• Most strains of E. coli are
harmless
• E. coli are pathogenic
AKA. can make you sick
An important part of a healthy
human intestinal tract
– E. coli being found in drinking water
E.coli can cause diarrhea, while others cause
urinary tract infections, respiratory illness,
and pneumonia, and other illnesses
CDC (2017)

4. Strains of E. coli
Large and diverse group of bacteria
Pathogenic E. coli strains are categorized into
pathotypes
This pathotype is the one most commonly heard
about in the news in association with foodborne
outbreaks.
STEC live in the guts of ruminant animals,
including cattle, goats, sheep, deer, and elk. STEC
that cause human illness generally do not make
animals sick.
Other kinds of animals, including pigs and birds,
sometimes pick up STEC from the environment
and may spread it. CDC (2017)
Six pathotypes are associated with diarrhea and collectively are
referred to as diarrheagenic E. coli.
 Shiga toxin-producing E. coli (STEC)—STEC may also be referred
to as Verocytotoxin-producing E. coli (VTEC) or
enterohemorrhagic E. coli (EHEC)
 The strain of Shiga toxin-producing E. coli O104:H4 that
caused a large outbreak in Europe in 2011 was frequently
referred to as EHEC
 Enterotoxigenic E. coli (ETEC)
 Enteropathogenic E. coli (EPEC)
 Enteroaggregative E. coli (EAEC)
 Enteroinvasive E. coli (EIEC)
 Diffusely adherent E. coli (DAEC)
CDC (2017)
Pathotypes

5. Differences between O157 STEC and Non-O157 STEC
O157 STEC non-O157 STEC
Older laboratory practices did not identify non-O157
infections
 non-O157 serogroups are less likely to cause severe
illness than E. coli O157
 E. coli serogroups in the STEC group, including E.
coli O145, are sometimes called "non-O157 STECs."
 Sometimes harmful , eg. E. coli O26 produces the
same type of toxins that E. coli O157 produces
 Less likely to lead to kidney problems (called
hemolytic uremic syndrome, or HUS).
 Identification of non-O157 STEC infections is more
complex
CDC (2017)
First identified as a pathogen in 1982
 Many other kinds. The most commonly identified
STEC in North America is E. coli O157:H7 (often
shortened to E. coli O157 or even just “O157”).
 Many other kinds (called serogroups) of STEC
cause disease
 STEC comes from studies of E. coli O157 infection
 E. coli cause disease by making a toxin called Shiga
toxin.
 Bacteria that make these toxins are called “Shiga
toxin-producing” E. coli
 Identification of O157 STEC infections is less
complex compared to non-O157 STEC
CDC (2017)

6. E.coli Transmission
Shiga toxin-producing E. coli (STEC)— O26 Mode: Contaminated water or food, or
through contact with animals or persons.
 People usually get sick from STEC (Shiga toxin-
producing E. coli) 2-8 days (average of 3-4 days)
after swallowing the organism (germ).
 Most people infected with STEC develop diarrhea
(often bloody) and abdominal cramps.
 Most people recover within a week.
 Some illnesses last longer and can be more severe,
resulting in a type of kidney failure called
hemolytic uremic syndrome (HUS).
 HUS can occur in people of any age, but is most
common in young children under 5 years, older
adults, and people with weakened immune
systems.
(CDC,2017)
People who experience these symptoms should seek
emergency medical care immediately.
STEC infection is usually diagnosed by testing of a stool
sample for Shiga toxins.
Symptoms of HUS can include fever, abdominal pain, pale
skin tone, fatigue and irritability, small, unexplained
bruises or bleeding from the nose and mouth, and
decreased urination.
Clinical laboratories are required in some states to send
Shiga toxin-positive specimens from ill people to the
state public health laboratory for identification of STEC
and PulseNet testing.
(CDC,2017)

7. Clinical Laboratories
 Clinical laboratories must test stool samples for
the presence of Shiga toxins.
 Then, the positive samples must be sent to public
health laboratories to look for non-O157 STEC.
 Clinical laboratories typically cannot identify non-
O157 STEC.
 Other non-O157 STEC serogroups that often cause
illness in people in the United States include O26,
O111, and O103.
 Investigators used whole genome sequencing, an
advanced laboratory technique, to get more
information about the DNA fingerprint of the STEC
O26 bacteria causing illness in both outbreaks
(Multistate Outbreak of E. coli O26 Infections
Linked to Chipotle Mexican Grill Restaurants)
 Whole genome sequencing (WGS) was performed
on STEC O26 isolates from 36 ill people from the
first outbreak. All 36 isolates were highly related
genetically to one another.
(CDC, 2017, U.S. Food & Drug Administration, 2017).

8. Historical outbreak
Multistate Outbreak of E. coli O26 Infections Linked to Chipotle Mexican Grill
Restaurants
Outbreak Investigative agencies
 U.S Food and Drug Administration
 Centers for Disease Control and Prevention (CDC)
 State and Local Health Departments
Investigated two outbreaks of E. coli O26 infections
Consumers who have recently become ill after eating at a Chipotle should contact their
health care provider.
Who is at risk
People of any age can become infected. Very young children and the elderly are more
likely than others to develop severe illness and HUS, but even healthy older children and
young adults can become seriously ill.
In this particular outbreak, the age range of ill patients is 1 - 67 years.
Who to contact in terms of the outbreak
Contact your healthcare provider if you have diarrhea that lasts for more than 3 days, or
is accompanied by high fever, blood in the stool, or so much vomiting that you cannot
keep liquids down and you pass very little urine.
The FDA encourages consumers with questions about food safety to call 1-888-
SAFEFOOD Monday through Friday between 10 a.m. and 4 p.m. Eastern time, or to
consult the FDA website.
( CDC,2017; U.S. Food & Drug Administration,2017).

9. E. coli O26 Outbreak
 As of January 27, 2016, the CDC reports a total of 55 people infected with
the outbreak strain of STEC (Shiga toxin producing E. coli) O26 from a total
of 11 states in the larger outbreak: California (3), Delaware (1), Illinois (1),
Kentucky (1), Maryland (1), Minnesota (2), New York (1), Ohio (3), Oregon
(13), Pennsylvania (2), and Washington (27).
 There have been 21 reported hospitalizations. The majority of these cases
were reported from Oregon and Washington during October 2015.
 In December 2015, the CDC reported five people infected in three states
with a different, rare strain of STEC O26: Kansas (1), North Dakota (1),
and Oklahoma (3). Interviews were conducted with five ill people, who all
reported eating at Chipotle Mexican Grill restaurants. There were no reports
of hemolytic uremic syndrome (HUS) and no deaths in either outbreak.
 In May 4, 2017, Multistate Outbreak of Shiga toxin-producing
Escherichia coli O157:H7 Infections Linked to I.M. Healthy Brand SoyNut
Butter. Case Count: 32
o States: 12 , Deaths: 0, Hospitalizations: 12, Recall: Yes
( CDC,2017; U.S. Food & Drug Administration,2017)

10. Epidemic curve or epi curve (Chipotle E. coli O26 Outbreak)
Onset- October 19,2015
End- November 8,2015
The 45 number of ill people reported from each state is as follows:
California (2), Minnesota (2), New York (1), Ohio (1), Oregon (13), and
Washington (26).
October 31, 2015 might not be reported yet due to the time it takes
between when a person becomes ill and when the illness is reported.
This takes an average of 2 to 3 weeks.
(Marler Clark. The Food Safety Law Firm, 2017)

11. Symptoms after Exposure
 The time between ingesting the STEC
bacteria and feeling sick is called the
“incubation period.”
 The incubation period is usually 3-4
days after the exposure, but may be
as short as 1 day or as long as 10 days.
 The symptoms often begin slowly with
mild belly pain or non-bloody
diarrhea that worsens over several
days.
 HUS, if it occurs, develops an average 7
days after the first symptoms, when
the diarrhea is improving.
( CDC,2017; U.S. Food & Drug Administration,2017).
The symptoms of STEC infections
vary for each person but often
include severe stomach cramps,
diarrhea (often bloody), and
vomiting.
 If there is fever, it usually is not very
high (less than 101˚F/less than
38.5˚C).
Most people get better within 5–7
days. Some infections are very mild,
but others are severe or even life-
threatening.

12. Sources of infection
 Contaminated food, especially undercooked ground beef, unpasteurized (raw) milk and juice,
soft cheeses made from raw milk, and raw fruits and vegetables (such as sprouts)
 Contaminated water, including drinking untreated water and swimming in contaminated water
 Animals and their environment: particularly cows, sheep, and goats. If you don’t wash your
hands carefully after touching an animal or its environment, you could get an E. coli infection
 Feces of infected people
 Because there are so many possible sources, for most people we can only guess.
 If your infection happens to be part of the about 20% of cases that are part of a recognized
outbreak, the health department might identify the source.
Food Safety.gov (2017).

13. How STEC Can Be Prevented
WASH YOUR HANDS thoroughly after using the bathroom or changing
diapers and before preparing or eating food.
WASH YOUR HANDS after contact with animals or their environments (at
farms, petting zoos, fairs, even your own backyard).
COOK meats thoroughly. Ground beef and meat that has been needle-
tenderized should be cooked to a temperature of at least 160°F/70˚C. It’s
best to use a thermometer, as color is not a very reliable indicator of
“doneness.”
AVOID raw milk, unpasteurized dairy products, and unpasteurized juices
(like fresh apple cider).
AVOID 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.
( CDC,2017; U.S. Food & Drug Administration,2017)

14. How STEC Can Be Prevented
For Retailers
Retailers should consult the FDA Food Code, a model code of
recommendations published by the FDA for safeguarding public
health, providing guidance to retail food industry to ensure food is
unadulterated and honestly presented when offered to the consumer.
State and local governments may enact regulations similar to that
proposed in the FDA Food Code with which retail establishments are
required to comply.
If retail outlets have specific questions, they should consult the
regulatory agency that issued their permit to operate.
( CDC,2017; U.S. Food & Drug Administration,2017).
For schools
School and work exclusion policies differ by local jurisdiction
( CDC,2017)

15. Summary
Source : Food, Water, Animals , Feces of Infected People
Incubation Period : 1 -10 days
Symptoms : Severe diarrhea that is often bloody, severe abdominal pain, and vomiting.
Usually, little or no fever is present. Symptoms of HUS include decreased urine production,
dark or tea-colored urine, and facial pallor.
Duration of illness : 5-10 days. Most people will be better in 6-8 days. If HUS develops, it
usually occurs after about 1 week
What to do: Drink plenty of fluids and get rest
Prevention:
• Avoid eating high-risk foods, especially undercooked ground beef, unpasteurized milk
or juice, soft cheeses made from unpasteurized milk, or alfalfa sprouts.
• Use a food thermometer to make sure that ground beef has reached a safe internal
temperature of 160° F.
• Wash hands before preparing food, after diapering infants, and after contact with cows,
sheep, or goats, their food or treats, or their living environment .
( CDC,2017; U.S. Food & Drug Administration,2017).

16. References
Centers for Disease Control and Prevention (2017). E.coli (Escherichia Coli). Retrieved from:
https://www.cdc.gov/ecoli/index.html
Centers for Disease Control and Prevention (2017). How to Report a Foodborne Illness - General Public.
Retrieved from:https://www.cdc.gov/foodsafety/outbreaks/investigating-outbreaks/report-
illness/public.html
Centers for Disease Control and Prevention (2017). Retrieved from: https://www.cdc.gov/ecoli/general/index.html
Food Safety.gov (2017). E. coli. Retrieved from: https://www.foodsafety.gov/poisoning/causes/bac
teriaviruses/ecoli/
Marler Clark. The Food Safety Law Firm (2017). How Big Will E. coli Outbreaks Linked To Chipotle and Costco
Taylor Farms Be?Retrieved from: http://www.foodpoisonjournal.com/foodborne-illness-
outbreaks/how-many-people-will-be-linked-to-chipotle-and-costco-taylor-farms-e-coli-
outbreaks/
U.S. Food & Drug Administration (2017). FDA Investigates Multistate Outbreak of E. coli O26 Infections
Linked to Chipotle Mexican Grill Restaurants. Retrieved from
https://www.fda.gov/Food/RecallsOutbreaksEmergencies/Outbreaks/ucm470410.htm#sympto
ms