Download E. coli - University of Yeditepe Faculty of Medicine, 2011

Food Poisoning
Assoc. Prof.Dr. Yesim Gurol
Percentage Change in 2012 compared to 2006-2008: Campylobacter-14%
increase, E. coli O157-no change, Listeria-no change, Salmonella-no change,
Vibrio-43% increase, Yersinia-no change
2012 rate per 100,000 Population: Campylobacter-14.30, E. coli O157-1.12,
Listeria-0.25, Salmonella-16.42, Vibrio-0.41, Yersinia-0.33
2020 target rate per 100,000 Population: Campylobacter-8.5, E. coli O1570.6, Listeria-0.2, Salmonella-11.4, Vibrio-0.2, Yersinia-0.3
Campylobacter
O Chicken is the most common food implicated as
the source of Campylobacter contamination.
O Any raw poultry - chicken, turkey, duck, goose
meat and its juices may contain Campylobacter,
including organic and “free range” products.
O Other foods include unpasteurized (raw) milk,
undercooked meats such as beef, pork, lamb,
and livestock offal, and occasionally shellfish,
fresh produce, and eggs.
O Most cases of Campylobacter infection
occur as isolated, sporadic events, and are
not usually part of large outbreaks.
O But, very large outbreaks (>1,000 illnesses)
of campylobacteriosis have been
documented, most often from consumption
of contaminated milk or unchlorinated water
supplies.
O C. jejuni is commonly present in the
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gastrointestinal tract of healthy cattle, pigs,
chickens, turkeys, ducks, and geese.
Direct exposure to feces from animals carrying
Campylobacter can lead to infection.
People have become ill from contact with
infected dogs and cats.
Pets that may carry Campylobacter include birds,
cats, dogs, hamsters, and turtles.
The organism is also occasionally isolated from
streams, lakes, ponds, and dairy wastewater
(lagoons).
O The incubation period for Campylobacteriosis
(the time between exposure to the bacteria and
onset of the first symptom) is typically two to five
days, but onset may occur in as few as two days
or as long as 10 days after ingestion of the
bacteria.
O The illness usually lasts no more than one week
but severe cases may persist for up to three
weeks, and about 25% of individuals experience
relapses of symptoms.
O Diarrhea is the most consistent and prominent
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manifestation of Campylobacter infection and is often
bloody.
Typical symptoms also include fever, nausea,
vomiting, abdominal pain, headache, and muscle
pain.
A majority of cases are mild, do not require
hospitalization, and are self-limited.
However, Campylobacter jejuni infection can be
severe and life-threatening.
It may cause appendicitis or infect other organs as
well as the blood stream.
It is estimated that about one in 1,000 cases of
Campylobacter infection results in death. Death is
more common when other diseases (for example,
cancer, liver disease, and immune deficiency
diseases) are present.
O Long-term consequences and complications can
sometimes result from a Campylobacter
infection.
O Some people may develop a rare disease that
affects the body’s nervous system following
infection. This disease is called Guillain-Barré
Syndrome (GBS).
O It begins several weeks after the diarrheal
illness, may last for weeks to months, and often
requires intensive care. Full recovery is common
but some affected individuals may be left with
mild to severe neurological damage.
O Two therapies, intravenous immunoglobulin
infusions and plasma exchange, may improve
the rate of recovery in patients with GBS.
O Miller Fisher Syndrome (MFS) is a related
neurological syndrome that can occur with a
Campylobacter infection. In MFS, the nerves of the
head are affected more than the nerves of the body.
O Another chronic condition that may be associated
with Campylobacter infection is a form of reactive
arthritis called Reiter’s Syndrome.
O Reiter’s Syndrome typically affects large weightbearing joints such as the knees and the lower back.
It is a complication that is strongly associated with a
particular genetic make-up; persons who have the
human lymphocyte antigen B27 (HLA-B27) are most
susceptible
O The single most important and reliable step
to preventing Campylobacteriosis is to
adequately cook all poultry products.
O Make sure that the thickest part of the bird
(the center of the breast) reaches 180°F or
higher.
O It is recommended that the temperature
reaches at least 165°F for stuffing and
170°F for ground poultry products, and that
thighs and wings be cooked until juices run
clear. Do not cook stuffing inside the bird.
O Irradiation within approved dosages has been shown
to destroy at least 99.9% of common foodborne
pathogens including Campylobacter, which are
associated with meat, poultry, and secondary
contamination of fresh produce.
O Transport meat and poultry home from the market in
the coolest part of the vehicle (generally the trunk in
winter and cab in summer).
O Defrost meat and poultry in the refrigerator. Place the
item on a low shelf, on a wide pan, lined with paper
towel; ensure that drippings do not land on foods
below. If there is not enough time to defrost in the
refrigerator, use the microwave.
O Make sure that other foods, such as fruits or
vegetables, do not come into contact with
cutting boards or knives that have been
used with raw meat or poultry.
O To avoid cross-contamination, carefully clean
all cutting boards, countertops, and utensils
with soap and hot water after preparing raw
meat or poultry.
O Rapidly cool leftovers. Never leave food out at room
temperature (either during preparation or after
cooking) for more than 2 hours.
O Avoid consuming raw milk and other unpasteurized
dairy products and untreated (not chlorinated or
boiled) surface water.
O Wash fruits and vegetables carefully, particularly if
they are eaten raw. If possible, vegetables and fruits
should be peeled.
O Wash hands thoroughly using soap and water,
concentrate on fingertips and nail creases, and dry
completely with a disposable paper towel after
contact with pets, especially puppies or farm animals;
before and after preparing food, especially poultry;
and after changing diapers or having contact with an
individual with an intestinal infection. Children should
always wash their hands on arrival home from school
or daycare.
Botulism
O Botulism is a rare but serious paralytic
illness caused by a nerve toxin that is
produced by the bacterium Clostridium
botulinum.
O Clostridium botulinum is the name of a
group of bacteria commonly found in soil.
O The bacteria are anaerobic, Gram-positive,
spore-forming rods that produce a potent
neurotoxin
O Sausages, meat products, canned
vegetables, and seafood products have
been the most frequent vehicles for
foodborne botulism.
O Classic symptoms of botulism include double vision,
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blurred vision, drooping eyelids, slurred speech,
difficulty swallowing, dry mouth, and muscle
weakness.
Infants with botulism appear lethargic, feed poorly,
are constipated, and have a weak cry and poor
muscle tone.
These are all symptoms of the muscle paralysis
caused by the bacterial toxin.
If untreated, these symptoms may progress to cause
paralysis of the arms, legs, trunk, and respiratory
muscles.
In foodborne botulism, symptoms generally begin 18
to 36 hours after consuming contaminated food, but
they can occur as early as 6 hours or as late as 10
days after consumption.
O Botulinum toxin causes flaccid paralysis by
blocking motor nerve terminals at the myoneural
junction.
O The flaccid paralysis progresses symmetrically
downward, usually starting with the eyes and
face, then moving to the throat, chest, and
extremities.
O When the diaphragm and chest muscles
become fully involved, respiration is inhibited
and unless the patient receives treatment in
time, death from asphyxia results.
O the most sensitive and widely used method
for detecting toxin is the mouse
neutralization test, which involves injecting
serum or stool into mice and looking for
signs of botulism. This test typically takes
48 hours.
O Culturing of specimens takes 5-7 days.
O If diagnosed early, foodborne botulism can
be treated with an antitoxin that blocks the
action of toxin circulating in the blood. This
can prevent patients from worsening, but
recovery still takes many weeks.
O While botulism has been known to cause
death due to respiratory failure
O The respiratory failure and paralysis that
occur with severe botulism may require a
patient to be on a ventilator for weeks, plus
intensive medical and nursing care.
O After several weeks, the paralysis slowly
improves.
O Infant botulism
O Infant botulism is more common in the spring and the
summer and is rare in the winter. Infants younger than
one year of age, particularly between the ages of two to
four months, are at highest risk. Symptoms include
muscle weakness, a weak cry, a poor suck (difficulty in
feeding), feeble crying, constipation, head lag, increased
heart rate and a decreased gag reflex.
O A baby with infant botulism is described as a "floppy
baby," as the baby will have weak muscles, especially in
the arms, legs and neck. Infant botulism has been
associated with the ingestion of honey.
O The United States Center for Disease Control suggests
that honey should not be given to infants under the age
of 6 months. The Honey Industry Council extends that
limit to one year of age to be extra safe. Honey is not an
essential food for infants and should not be given.
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Unlike adults, infants younger than 12 months are vulnerable to
Clostridium botulinum bacteria colonizing (growing inside) the large
intestine.
The disease starts when an infant swallows spores at a moment in
time when the baby's large intestine is vulnerable to spore germination
and toxin production.
It is thought that most infants are exposed by swallowing sporecontaining dust which is naturally present in the environment.
The spores are found in honey and honey has been clearly linked to
infant botulism. Other foodstuffs (such as corn syrup) have been
suggested as sources but links to other foods are uncertain or
disproven. For most cases of infant botulism, no specific source of C.
botulinum spores is ever identified.
After being swallowed, spores can germinate in the intestine and, as
the bacteria grow, they produce botulinum toxin that is then absorbed
into the infant's body.
Although exposure to the spores is very common if not universal in
various parts of the world, only rarely do the bacteria manage to get
inside an infant at a vulnerable age, germinate, and create the toxin.
O Any food that is conducive to outgrowth and toxin
production, that when processed allows spore
survival, and is not subsequently heated before
consumption, can be associated with botulism.
O Almost any type of food that is not very acidic (pH
above 4.6) can support growth and toxin production
by C. botulinum.
O Botulinal toxin has been demonstrated in a
considerable variety of foods, such as canned corn,
peppers, green beans, soups, beets, asparagus,
mushrooms, ripe olives, spinach, tuna fish, chicken
and chicken livers and liver pate, and luncheon
meats, ham, sausage, stuffed eggplant, lobster, and
smoked and salted fish.
O Botulinum toxin is heat-labile, or unstable if
heated to a certain temperature, and can be
destroyed if heated and held at 80 degrees
Centigrade (176 degrees Fahrenheit) for ten
minutes or longer.
Salmonella
O Salmonella is one of the most common
enteric (intestinal) infections
O Salmonellosis – the disease caused by
Salmonella – is the second most common
bacterial foodborne illness after
Campylobacter infection
O Salmonella infection occurs when bacteria are ingested,
typically from food derived from infected animals, but
infection can also occur by ingesting the feces of an
infected animal or person.
O Food sources include raw or undercooked eggs/egg
products, raw milk or raw milk products, contaminated
water, meat and meat products, and poultry.
O Raw fruits and vegetables contaminated during slicing
have been implicated in several foodborne outbreaks, as
have foods contaminated by food handlers who did not
adhere to proper hygienic standards and practice proper
handwashing techniques.
O The acute symptoms of Salmonella
gastroenteritis include the sudden onset of
nausea, abdominal cramping, and bloody
diarrhea with mucous.
O Fever is almost always a symptom. Vomiting
is less common than diarrhea.
O Headaches, myalgias (muscle pain), and
arthralgias (joint pain) are often reported as
well.
O The onset of symptoms usually occurs within
6 to 72 hours after the ingestion of
Salmonella bacteria. The infectious dose is
small, probably from 15 to 20 cells.
O Reiter’s Syndrome, which includes and is
sometimes referred to as “reactive arthritis,” is
an uncommon, but debilitating, result of
Salmonella infection.
O The symptoms of Reiter’s Syndrome usually
occur between one and three weeks after
infection, and include at least two of three
seemingly unrelated symptoms: reactive
arthritis, conjunctivitis (eye irritation), and
urinary tract infection.
O The arthritis associated with Reiter’s Syndrome
typically affects the knees, ankles, and feet,
causing pain and swelling.
O Salmonella infections usually resolve in five
to seven days, and many times require no
treatment, unless the affected person
becomes severely dehydrated or the
infection spreads from the intestines
O To prevent salmonellosis, cook poultry, ground beef, and
eggs thoroughly before eating. In order to ensure that eggs
do not contain viable Salmonella they must be cooked at
least until the yoke is solid. Meat and poultry must reach
160ºF or higher throughout. Be particularly careful with
foods prepared for infants, the elderly, and those with a
compromised immune system, including diabetics, pregnant
women, HIV/AIDS patients, cancer patients, and transplant
recipients.
O Do not eat or drink foods containing raw eggs, such as
homemade eggnog and hollandaise sauce. Avoid drinking
raw (unpasteurized) milk or products made from raw milk.
O Wash hands, kitchen work surfaces, and utensils with soap
and water immediately after they have been in contact with
foods of animal origin. Also, wash hands with soap after
handling reptiles, amphibians, or birds, or after contact with
pet feces. Infants and immune-compromised persons should
have no direct or indirect contact with such pets.
Shigella
O Shigella is a bacterium that can cause
sudden and severe diarrhea (gastroenteritis)
in humans.
O Shigellosis is the name of the disease that
Shigella causes. The illness is also known as
“bacillary dysentery.”
O Shigella bacteria are found in the excrement
(feces) of infected individuals, and cause
illness when ingested.
O Infectious material can be spread to new
cases by person-to-person contact or via
contaminated food or water
O Infected food workers can contaminate food,
or food can become contaminated during
processing.
O Most people who are infected with Shigella
develop diarrhea, fever, and abdominal
cramps. The severity of illness ranges from
mild to very severe diarrhea. Diarrhea is
bloody 25-50 percent of the time and most
often contains mucus. Rectal spasms are
common.
O The illness, shigellosis, starts 12 hours to six
days, usually one to two days, after exposure
to the bacterium. Dehydration is also a
common symptom.
O Frequent and careful hand washing with soap
and water should be done by both the ill
individual and anyone who is in contact with that
person.
O Supervised hand washing of all children should
be followed in day care centers and as soon as
children return home.
O Children’s handwashing should be supervised in
daycare centers, and children should wash
hands after returning home. Young children with
a Shigella infection, or with diarrhea of any
cause, should not be in contact with uninfected
children.
Staphylococcus aureus
O Foods that are frequently a problem with
staphylococcal food poisoning include meat
and meat products; poultry and egg
products; salads such as egg, tuna, chicken,
potato, and macaroni; bakery products such
as cream-filled pastries, cream pies, and
chocolate eclairs; sandwich fillings; and milk
and dairy products.
O Foods that require considerable handling
during preparation and that are kept at
slightly elevated temperatures after
preparation are frequently involved in
staphylococcal food poisoning.
O Staph may also be present in raw milk and
raw milk products. Staph can cause mastitis
in dairy cows, and other infections in meat
animals. In this way, such meat sources may
cause staph outbreaks in people.
O Some S. aureus strains are able to produce
staphylococcal enterotoxins (SEs) and are
the causative agents of staphylococcal food
poisonings. Unlike C. perfringens, C.
botulinum, and B. cereus, S. aureus does
not form spores.
O Thus, S. aureus contamination can be
readily avoided by heat treatment of food.
Nevertheless, it remains a major cause of
FBD because it can contaminate food
products during preparation and processing.
O Staphylococcal toxins are fast acting, sometimes
causing illness in as little as 30 minutes. Symptoms
usually develop within one to six hours after eating
contaminated food. Patients typically experience
several of the following: nausea, vomiting, stomach
cramps, and diarrhea. The illness is usually mild and
most patients recover after one to three days. In a
small minority of patients the illness may be more
severe.
Vibrio parahaemolyticus
O In Asia, V. parahaemolyticus is a common cause of
foodborne disease
O Most people become infected by eating raw or
undercooked shellfish, particularly oysters. Less
commonly, this organism can cause an infection in
the skin when an open wound is exposed to warm
seawater.
O When ingested, V. parahaemolyticus causes watery
diarrhea often with abdominal cramping, nausea,
vomiting fever and chills. Usually these symptoms
occur within 24 hours of ingestion. Illness is usually
self-limited and lasts 3 days. Severe disease is rare
and occurs more commonly in persons with
weakened immune systems.
Bacillus cereus
O One type is characterized by nausea and vomiting and
abdominal cramps and has an incubation period of 1 to
6 hours. It resembles Staphylococcus aureus food
poisoning in its symptoms and incubation period. This is
the "short-incubation" or emetic form of the disease.
O The second type is manifested primarily by abdominal
cramps and diarrhea with an incubation period of 8 to
16 hours. Diarrhea may be a small volume or profuse
and watery. This type is referred to as the "longincubation" or diarrheal form of the disease, and it
resembles more food poisoning caused by Clostridium
perfringens. In either type, the illness usually lasts less
than 24 hours after onset. In a few patients symptoms
may last longer.
O Starchy foods such as rice, macaroni and potato dishes
are most often involved. The spores may be present on
raw foods, and their ability to survive high cooking
temperatures requires that cooked foods be served hot
or cooled rapidly to prevent the growth of this bacteria.
Clostridium perfringens
O C. perfringens is found in soil, dust and the
gastrointestinal tracts of animals and man. When food
containing a large number of C. perfringens is
consumed, the bacteria produce a toxin in the intestinal
tract that causes illness.
O C. perfringens can exist as a heat-resistant spore, so it
may survive cooking and grow to large numbers if the
cooked food is held between 40 degrees F and 140
degrees F for an extensive time period.
O Meat and poultry dishes, sauces and gravies are the
foods most frequently involved. Hot foods should be
served immediately or held above 140 degrees F.
O When refrigerating large volumes of gravies, meat
dishes, etc., divide them into small portions so they will
cool rapidly. The food should be reheated to 165o F.
prior to serving.
Yersinia enterocolitica
O Y. enterocolitica is commonly present in
foods but with the exception of pork, most
isolates do not cause disease. Like Listeria
this organism is also one that can grow at
refrigeration temperatures. It is sensitive to
heat (5%) and acidity (pH 4.6), and will
normally be inactivated by environmental
conditions that will kill Salmonellae
E.Coli O157:H7
O E. coli O157:H7 is the source of an
estimated 73,000 illnesses, 2,000
hospitalizations, and 60 deaths in the
United States every year
O E. coli O157:H7 was firmly associated
with hemorrhagic colitis. The majority of
infections are thought to be food-related,
although E. coli O157:H7 accounts for
less than one percent of all food
poisoning cases.
O E. coli O157:H7 bacteria are believed to mostly live in
the intestines of cattle but have also been found in
the intestines of chickens, deer, sheep, goats, and
pigs. E. coli O157:H7 does not make the animals that
carry it ill; the animals are merely the reservoir for the
bacterium.
O While a large number of foodborne illness outbreaks
associated with E. coli O157:H7 have involved ground
beef, such outbreaks have been increasingly
associated with fresh produce, such as lettuce and
spinach, but outbreaks have also been traced to
unpasteurized apple and orange juices, raw milk,
alfalfa sprouts, and water.
O Person-to-person transmission of the bacterium has
been documented in homes, hospitals, daycare
centers, nursing homes and many other locations.
O characterized by the sudden onset of abdominal pain
and severe cramps, followed within 24 hours by
diarrhea.
O As the disease progresses, the diarrhea becomes
watery and then may become grossly bloody.
O Vomiting, and rarely fever, can also be symptoms. The
incubation period for the illness (the period from
ingestion of the bacterium to the start of symptoms)
is typically three to nine days, although slightly
shorter and longer periods are not that unusual.
O An incubation period of less than 24 hours would be
unusual, however. In most infected individuals, the
intestinal illness lasts about a week and resolves
without any long-term problems.
O about five to ten percent of infected individuals
develop hemolytic uremic syndrome (HUS), a
severe, life-threatening complication of E. coli
O157:H7 bacterial infection. HUS develops
when E. coli’s toxins enter the circulation by
binding to special receptors.
O During HUS, red blood cells are destroyed and
cellular debris accumulates within the blood
vessels while the body’s clot-breaking
mechanisms are disrupted, causing blockage of
the terminal arterioles and capillaries
(microcirculation) of most of the major body
organs, commonly the heart, brain, kidneys,
pancreas and adrenals.
O Some organs appear more susceptible than
others to the damage caused by these
toxins. These organs include the kidney,
pancreas, and brain.
O Eating undercooked ground beef has
historically been the most important risk
factor for acquiring E. coli O157:H7
O Persons who cook ground beef without using
a thermometer can decrease their risk of
illness by not eating ground beef patties that
are still pink in the middle
O Avoid spreading harmful bacteria in your
kitchen. Keep raw meat separate from
ready-to-eat foods.
O Wash hands, counters, and utensils with hot
soapy water after they touch raw meat.
O Never place cooked hamburgers or ground
beef on the unwashed plate that held raw
patties.
O Wash meat thermometers in between tests
of patties that require further cooking.
O Drink only pasteurized milk or juice. Commercial juice
with an extended shelf life that is sold at room
temperature (such as juice in cardboard boxes or
vacuum-sealed juice in glass containers) has been
pasteurized, although this is generally not indicated on
the label. Most juice concentrates are also heated
sufficiently to kill pathogens.
O Fruits and vegetables, especially if not cooked, should
be washed thoroughly. Children under five years of age,
people with weakened immune systems, and elderly
persons should avoid eating sprouts until their safety
can be assured. Methods to decontaminate alfalfa
seeds and sprouts are being investigated.
O Drink municipal water that has been treated with
chlorine or other effective disinfectants, or bottled water
that has be sterilized with ozone or reverse osmosis
(almost all major brands use one or the other method).
O Avoid swallowing lake or pool water while swimming,
especially pool water in public swimming facilities.
O Avoid petting zoos and other animal exhibits unless
there are good hand washing facilities available and
other sanitation measures have been taken. Wash
your hands and your children’s hands after touching
animals.
O Make sure that persons with diarrhea, especially
children, wash their hands carefully with soap after
bowel movements to reduce the risk of spreading
infection, and that persons wash hands after
changing soiled diapers. Anyone with diarrhea should
avoid swimming in public pools or lakes, sharing
baths with others, and preparing food for others.
STEC infection
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Some kinds of E. coli cause disease by making a toxin called Shiga
toxin. The bacteria that make these toxins are called
“Shiga toxin-producing” E. coli (STEC)
verocytotoxic E. coli (VTEC)
enterohemorrhagic E. coli (EHEC)
“non-O157 STEC.”
E. coli serogroups O26, O111, and O103
O non-O157 serogroup less likely to cause severe
illness than E. coli O157
O some non-O157 STEC serogroups can cause the
most severe manifestations of STEC illness.
O incubation period is usually 3-4 days after the exposure,
O 1 day or 10 days.
O The symptoms often begin slowly with mild belly pain or
non-bloody diarrhea that worsens over several days.
O HUS, if it occurs, develops an average 7 days after the
first symptoms, when the diarrhea is improving.
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Oral-feacal
consumption of contaminated food, consumption of unpasteurized (raw)
milk, consumption of water that has not been disinfected,
contact with cattle, or contact with the feces of infected people.
unpasteurized (raw) milk, unpasteurized apple cider,
soft cheeses made from raw milk.
the contact is pretty obvious (working with cows at a dairy or changing
diapers, for example),
like eating an undercooked hamburger or a contaminated piece of lettuce
People have gotten infected by swallowing lake water while swimming,
touching the environment in petting zoos and other animal exhibits,
by eating food prepared by people who did not wash their hands well after
using the toilet.
O STEC typically disappear from the feces by the time the illiness
is resolved, but may be shed for several weeks, even after
symptoms go away.
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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.
Campylobacter
These bacteria are very common in
poultry. It is believed that half of all raw
chicken is contaminated with it. Other
sources of infection include unpasteurized
milk and contaminated water.
Clostridium botulinum
This bacterium is common in soil, and can lead to
a deadly illness called botulism. Food-borne
botulism is rare because the organism needs
specific conditions in order to produce toxins;
namely a temperature above 38° Fahrenheit and a
lack of oxygen. Poorly canned vegetables and
fruits are a potential source for this type of food
poisoning, but modern canning methods have
almost done away with the problem. Honey can
be a source of infant botulism.
E. coli
These bacteria are the most common cause of
traveler’s diarrhea. Drinking water—even ice
cubes floating in a drink—or eating peeled fruit
while in a foreign country can lead to infection.
Undercooked ground beef and unpasteurized
milk are other havens for E. coli. There have been
several recent nationwide E. coli outbreaks in
which the culprit was a vegetable, rather than
meat or water. An outbreak in 2006 affected more
than 150 people and resulted in 3 deaths. Public
health officials eventually traced the outbreak to
raw spinach, but the ultimate source of
contamination remains unknown. .
Listeria monocytogenes
This bacterium is usually picked up from
soft cheeses, undercooked meats, and
foods prepared in delicatessens
Salmonella
These bacteria are commonly found in
raw or undercooked meat, poultry, and
raw eggs.
Shigella
These bacteria thrive in food that is left
out for long periods
Staphylococcus
These bacteria are usually picked up from
mayonnaise-based salads (tuna salad, potato
salad, egg salad) and cream-filled desserts.
Vibrio
Normal marine bacteria. Usually acquired
by eating raw mollusks
Staphylococ
ci
Intense vomiting and
watery diarrhea start 1-4
hours after ingestion and
last as long as 24-48
hours.
Enterotoxin acts
on receptors in
gut that transmit
impulses to
medullary
centers.
Symptomatic
treatment
B cereus
Contaminated fried rice
(emetic)
Meatballs (diarrheal)
Emetic enterotoxin
(short incubation and
duration)
Diarrheal enterotoxin
(long incubation and
duration) -
Symptomatic
treatment
C perfringens
Inadequately cooked meat,
poultry
Acute onset of abdominal
cramps with diarrhea starts
8-24 hours after ingestion.
Vomiting is rare
Enterotoxin
produced in the gut,
and food causes
hypersecretion in
the small intestine.
Symptomatic
treatment
Canned foods (eg, smoked
fish, mushrooms, vegetables,
honey)
Descending weakness and
paralysis start 1-4 days after
ingestion, followed by
constipation.
Mortality is very high.
Toxin absorbed from
the gut blocks the
release of acetylcholine
in the neuromuscular
junction.
Respiratory support
C botulinum
Intravenous trivalent
antitoxin from CDC
Listeria
monocytogenes
Raw and pasteurized milk, soft cheeses, raw
vegetables, shrimp
Highly motile, heat-resistant,
Gram-positive organism
Enterotoxic E coli
(eg, traveler's
diarrhea)
Contaminated water and food (eg, salad,
cheese, meat)
Enterotoxin causes
hypersecretion in small and
large intestine via guanylate
cyclase activation.
Supportive treatment
Cytotoxin results in endothelial
damage and leads to platelet
aggregation and microvascular
fibrin thrombi
Supportive treatment
Contaminated imported cheese
Enterotoxin produces secretion
Supportive treatment
Usually watery diarrhea (some may present
with dysentery)
Shiga-like toxin facilitates
invasion.
No antibiotics
Acute-onset watery diarrhea starts 24-48
hours after ingestion.
No antibiotics
Concomitant vomiting and abdominal
cramps may be present. It lasts for 1-2 days
Enterohemorrhagi
c E coli (eg, E coli
O157:H7)
Improperly cooked hamburger meat and
recently spinach
Most common isolate pathogen in bloody
diarrhea starts 3-4 days after ingestion.
No antibiotics
Usually progresses from watery to bloody
diarrhea. It lasts for 3-8 days
May be complicated by HUS or TTP
Enteroinvasive E
coli
Enteroaggregative E coli
Implicated in traveler's diarrhea
in developing countries
Bacteria clump on the cell
surfaces
Ciprofloxacin may shorten
duration and eradicate the
organism
Enterotoxin causes
hypersecretion in small
intestine.
Positive stool culture
Raw and improperly cooked
seafood (ie, mollusks and
crustaceans)
Enterotoxin causes
hypersecretion in small
intestine.
Positive stool culture
Explosive watery diarrhea
starts 8-24 hours after ingestion.
It lasts for 3-5 days.
Hemolytic toxin is lethal.
Domestic animals, cattle,
chickens
Uncertain about endotoxin
production and invasion
Can cause bloody diarrhea
V cholera
Contaminated water and food
Large amount of nonbloody
diarrhea starts 8-24 hours after
ingestion. It lasts for 3-5 days.
V parahaemolyticus
C jejuni
Fecal-oral transmission in
humans
Foul-smelling watery diarrhea
followed by bloody diarrhea
Prompt replacement of fluids
and electrolytes
Prompt replacement of fluids
and electrolytes
Culture in special media at
42°C
Shigella
Salmonella
Yersinia
Potato, egg salad,
lettuce, vegetables, milk,
ice cream, and water
Organisms invade
epithelial cells and
produce toxins.
Abrupt onset of bloody
diarrhea, cramps,
tenesmus, and fever
starts 12-30 hours after
ingestion.
Infective dose is 102-103
organisms.
Beef, poultry, eggs, and
diary products
Abrupt onset of
moderate-to-large
amount of diarrhea with
low-grade fever; in
some cases, bloody
diarrhea
Invasion but no toxin
production
Pets; transmission in
humans by fecal-oral
route or contaminated
milk or ice cream
Gastroenteritis and
mesenteric adenitis
PMNs and blood in
stool
Direct invasion and
Positive stool culture
Acute abdominal pain,
diarrhea, and fever
(enterocolitis)
Polymorphonuclear
leukocytes (PMNs),
blood, and mucus in
stool
Positive stool culture
Enterotoxin-mediated
diarrhea followed by
invasion
(dysentery/colitis)
Positive stool culture
Antibiotic for systemic
infection
enterotoxin