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The Microworld
Foodborne Diseases
Definitions
Foodborne illness – Illness carried or
transmitted to people by food.
Foodborne Infections – result of a
person eating food containing
pathogens, which then grow in the
intestines and cause illness.
( typically symptoms of foodborne illness
do not appear immediately)
Definitions
Foodborne intoxication
Result of a person eating food containing
toxins (poisons) that cause an illness.
The toxins my have been produced by
pathogens found on the food or may be
result of a chemical contamination, or
part of the natural food.
Appear quickly, within a few hours.
Definitions
Foodborne Toxin-mediated
(Toxicoinfection) infection
Result of a person eating food containing
pathogens which then produce illnesscausing
toxins in the intestines.
Gastrointestinal illness
Illness relating to the stomach or intestine
Campylobacter jejuni
Foodborne Infection
Microaerophilic
Curved Rod shape
#1 cause of bacterial foodborne illness in U.S.
Est. 2-4 million cases a year
Guillian Barré Syndrome
Neuromuscular disease
Campylobacter jejuni
Common Foods
Poultry
Contaminated Water
Prevention Measures
Cook Food particularly poultry, to required
minimum internal temperatures
Prevent Cross-contamination between raw
and ready-to-eat food.
Salmonella spp.
Illness: Salmonlellosis
2,300 serovars
Rod shaped, Non-spore forming
Facultative Anaerobe
Asymptomatic carrier
Carry pathogenic organism without
symptoms
“typhoid mary” – Mary Malone
53 people, 7 outbreaks, 3 deaths
Classification based on Disease
Syndrome
1.
Typhoid fever
2.
Paratyphoid fever
3.
Salmonellosis (Gastroenteritis)
Salmonella typhi
Habitat: GI tract of humans, polluted H2O
Vaccine
Poor Sanitation
Not common in U.S.
Infectious dose – 1-10 cells
Typhoid fever (Typhoid fever – once you have
it cant get it again)
high fever – 105° F
Severe Diarrhea
Vomiting
Dehydration
Cartiovascular collapse
Death
Salmonella paratyphi
Habitat: GI tract of humans, Polluted
H2O
Similar to typhoid fever but not as
severe
Disease : paratyphiod fever
Salmonellosis/Gastroenteritis
Foodborne Infection
Severity depends on health, age, # cells
Onset: 6 – 72 hrs
Duration: 2-3 days
Symptoms
Nausea, Vomiting, Diarrhea
Headache, Fever, Chills
Sweating, Weakness
Salmonellosis/Gastroenteritis
Carriers/Implicated foods
Poultry – meat and eggs
Cattle – beef and dairy prod.
Swine – pork
RTE foods
Other implicated foods
Wildgame
Orange juice
Alfalfa sprouts
Nuts – Snickers
Cantaloupes/Melons
Control of Salmonella
1.
2.
Personal hygiene – Hand washing
Cooking/Pasteurization
Poultry 165°F for 15 sec.
Eggs
Raw or undercooked or minimally cooked eggs –
pasteurized egg product
Keep adequately refrigerated will prevent any
Salmonella present in the eggs from growing to
higher numbers
3.
Avoid Cross Contamination
Shigella spp.
Rod Shaped
Habitat – GI tract of humans
Small infective dose – 10 cells
Easily transmissible because of low
infectious dose
Foodborne infection
Disease: Shigellosis or Bacilliary
dysentary
Shigellosis
Disease of Armys, Asylums, and Prisons
Concentrated people
Dorms, school systems, military
Symptoms
Nausea, Vomiting
Abdominal Pain
Diarrhea (watery/bloody)
Fever/Chills
Prostration, Fatigue
Sever cases - HUS
Shigellosis
Onset: 1-3 days
Duration: 4 days or more
Most often , BUT Not always self limiting
Sometimes must use antibiotics
Transmited via fecal-oral route
Food Infection
Shigellosis
Implicated Foods
Heavily Handled Foods
Salads/Lettuce
Ready to Eat Meat products
Control
Personal Hygeine – Hand Washing
Exclude infected foodhandlers
Control flies inside and outside the
establishment
Listeria monocytogenes
Rod
Non-spore forming
Psychrophile
Anaerobic
Habitat:
Decaying vegetative mater
Soil
GI tract of animals and humans
Cool, wet, damp processing environments
Listeria monocytogenes
Disease: Listeriosis
Onset: 3 to 70 days
Occurs most frequently in at risk
populations
Opportunistic Pathogen
Prevention:
Watch sell-by date
Prevent cross-contamination
Cook meat to proper temperature
Listeria monocytogenes
Symptoms
Flu-like symptoms
in healthy adults
Fever
Nausea
Vommiting
Diarrhea
Chills
At Risk (in addition
to reg. symptoms)
Rash
Backache
Headache
Septicemia
Meningitis
Encephalitis
Abortions
Listeria monocytogenes
Implicated Foods
Soft mexican style cheese
Luncheon Meat
Frankfurtures
1st documented outbreak in 1982
160 people ill
Cooked products – eliminates competing bacteria
Cooked products – eliminates competing
bacteria
Vibrio
Rods
Foodborne Infection
Non-spore Forming
Types:
V. parahaemolyticus
V. vulnificus
V. cholerae
V.alginolyticus
Illness: Vibrio parahaemolyticus Gastroenteritis
Japan – most common cause of FBI
Implicated Foods:
Raw or partially cooked oysters
Vibrio vulnificus
Diseases:
Vibrio vulnificus Primary Septicemia- Most
common
At risk populations (liver disease) – 70 to 80%
mortality
Fever/Chills
Nausea
Skin Lesions
Diarrhea and vomiting
Vibrio vulnificus Gastroenteritis – Less common
Diarrhea
Abdominal cramps
Vibrio
Vibrio cholerae
Disease: Cholera
Habitat: GI tract of humans
Symptoms
High fever, Severe watery diarrhea
Dehydration, Cardiovascular collapse, Death
Pandemic – worldwide outbreak
Vibrio alginolyticus
Habitat: Marine Environment
Causes Wound Infections
Soft tissue, Ear
Vibrio
Implicated Food: Raw or partially cooked
shellfish (Bivalves- two shells)
Bioaccumulators – accumulate toxins
Prevention Measures
Purchase oysters from approved source
Cook oysters to required minimum internal
temperatures
Light steaming improves safety but not fool proof.
• Must post WARNING:
– Eating raw Shellfish could be hazardous to
heath
– At-risk populations should not eat raw
Shellfish
• Shellfish Stock ID tags
– Live, raw shellfish (shell still closed)
– ID tags
•
•
•
•
When harvested
Where harvested
By whom harvested
Packer
Foodborne intoxication
Endotoxin – Toxin that is produced by a
cell and is then expelled outside of the
cell
Exotoxin – Toxin that is produced and
remains inside the cell until the ruptures
(cell death) and is then released
Types of toxins based on target organ
Enterotoxin – of the intestines; GI tract
Neurotoxin – Affects the CNS
Hepatotoxin – Affects the liver
Nephrotoxin – Affects the kidneys
Bacillus cereus
Spore Former – Produces an
Endospore
Habitat: Soil
Facultative Aerobe
Cells – Rod shape
Bacillus cereus
Symptoms
Watery diarrhea
Abdominal cramps/Pain
Nausea,
Vomiting
Common Foods
Cooked Corn
Cooked Potatoes
Cooked Vegetables
Meat Products
Cooked Rice dishes:
Fried Rice
Rice Pudding
Starchy Foods
Potatoes
Pastas
B. Cereus – emetic type
Symptoms
Nausea
Vomiting
Diarrhea, occasionally
Abdominal cramps,
occasionally
Onset: 15 min – 6 hrs
Duration: less than 24 hr
Common Foods
Cooked Rice dishes:
Fried Rice
Rice Pudding
Starchy Foods
Potatoes
Pastas
Prevention Measures
Cook food to required minimum internal
temperature
Prevent Bacterial Growth and Toxin Production
Hold food at the proper
temperature
Cool food Properly
Staphylococcus aureus
Cocci shape
Habitat: Hair, nose, throat, feathers and
sores/boils/pimples
Disease: Staphylococcal Gastroenteritis
FB Intoxication – Exotoxin
Enterotoxin
Symptoms:
Nausea, Vomiting, Diarrhea
Abdominal pain, Headache
Sweating, with a decrease in body temp.
Staphylococcus aureus
Implicated Foods
High protein foods which are cooked
Meat, poultry, gravies, puddings, egg products
Salads containing PHF (egg, tuna, chicken,
macaroni)
Common associations
Temperature abuse
Foods on hot holding lines not hot enough
Refrigeration not cold enough
Re-contamination from humans
Staphylococcus aureus
Prevention Measures
Personal Hygiene
Properly coved cuts on hands and arms
Restrict infected food handlers from working
with or around food or food equipment
Minimize the time food spends in the
Temperature Danger Zone
Cook, hold and cool food properly
Clostridium botulinum
Rod shaped
Obligate anaerobe
Spore Former
Habitat: Soil, Air, Water
Food Intoxication
Exotoxins
All neurotoxins
Heat stable to a point (Boil for 10 min)
Clostridium botulinum
Disease: Botulism
Botulism toxin mechanism
Blocks the release of a neurotransmitter
Acetylcholine
Causes Paralysis
Symptoms
Nausea, Vomiting, Abdominal pain
Diarrhea (constipation), Headache
Diplopia, Speech impairment, Incordination
Paralysis, Cardiac Failure
Respiratory Failure, Death
Clostridium botulinum
Implicated Foods
Improperly canned foods (often home-canned)
FDA regulation – NO home-canned foods may be served
Modified Atmosphere Packaging
Controlled Atmosphere
Other Foods
Baked potatoes
Garlic-in-oil
Sautéed onions
Processed meats
Nitrates/Nitrites
Clostridium botulinum
Control
Avoid temperature abuse of Potentially
Hazardous Food
Use only commercially prepared canned
foods
Infant botulism – toxin mediated infection
“Floppy Baby Syndrome”
Underdeveloped gut flora
Honey/Syrup – not under 1 yr of age
Clostridium perfringens
Rod shaped
Obligate anaerobe – NO O2
Spore Former
Habitat: Ubiquitous - Soil, Air, Water, GI tract
Toxin-mediated infection
Doesn’t compete well
Double every 8 minutes in right environment
2-6% of humans are asymptomatic carriers
Clostridium perfringens
Disease:
Clostridium perfringens Gastroenteritis
Symptoms:
Violent cramps
Explosive diarrhea – due to gas production
Headache
Nausea
NO vomiting
Escherichia coli
Both pathogenic and non-pathogenic
serotypes
Habitat: GI tract of humans and animals
Rod shape
Non-spore forming
5 types of Enterovirulent E. coli
Enterotoxigenic
Enteropathogenic
Enterohemorrhagic
Enteroaggregative
-- Enteroinvasive
• Enterotoxigenic – ETEC
– Toxin-mediated infection
– Disease – Traveler’s Diarrhea
– Symptoms:
• Abdominal pain, Nausea, Vomiting, Watery Diarrhea,
and Fever
– Polluted Water
– Enteropathogenic – EPEC
– Severe form of infant diarrhea
– 1940s & 1950s high mortality rate
• Enteroaggregative - EAggEC
– Infant diarrhea
• Enteroinvasive – EIEC
– Bacilliary Dysentary
– Invades intestinal cells
– Symptoms
•
•
•
•
•
Bloody diarrhea
Nausea
Vomiting
Fever
Chills
Enterohemorrhagic - EHEC
Shiga toxin-producing E. coli
*E. coli O157:H7 (Shiga like toxin I and II)
O26:H11
O111:H8
Habitat: GI tract of cattle and humans
Common Associated foods
Ground beef (raw and undercooked)
“Mature beef” – older/dairy cattle
Contaminated produce
EHEC
• Diseases
– Hemorragic Colitis - HC
• More common
• Affects colon
– Hemolytic Uremic Syndrome - HUS
• Affects Kidneys
• Septcemia - “blood poisoning”
• Infective dose - < 50 cells
•
Major Outbreak
– Jack-In-the-Box
•
•
•
600 ill
3 deaths
Control
1. Ground Beef – Cook Internal Temp
–
–
–
–
FDA 155°F for 15 sec.
USDA 160°F for 15 sec
@ risk/medicare - 165°F for 15 sec
Nitrates
2. Pasturization of Juices
3. Hand Washing
4. Avoid Cross-contamination
Illnesses caused by
Viruses
Virus
Non-living
Must have a host to reproduce
Do not consume nutrients
Do not excrete waste products
Protein coat with DNA/RNA
Smallest microbial contaminant
Submicroscopic
Virus
Low Infective Doses
Many virus resistant to:
Fairly communicable through foods and
direct contact
Sanitizers
Freezing
Heat
Resistance varies greatly
Hepatitis A
Infectious Hepatitis A
Multiple types of Hepatitis A,B,C,D,E,F
Disease of the liver
A – only one relevant to food service
Sources of A
Human GI tract
--RTE foods
• Deli meat
Polluted H2O
• Produce
Raw Shellfish
• Salads
Raw fish / Crustaceans
Hepatitis A
Disease can vary greatly from mild to
life threatening
Nausea
Diarrhea
Vomiting
*Jaundice
-- Fever
-- Fatigue
-- Abdominal Pain
-- liver enlargement
Hepatitis A
Can still be infectious weeks after symptoms
gone
Spread via fecal-oral route
Prevention
Good Personal Hygeine
Exclude all infected workers
NO raw shellfish
Purchase from reputable suppliers
Steam shellfish for 90 sec (184-194° F/ 4min)
Norovirus
Disease: Norovirus Gastroenteritis
1st outbreak – Norwok, Ohio
Contaminated drinking water
Non-life threatening
Symptoms
Diarrhea, Vomiting
Cramps, Nausea
Headache, Anorexia
EXTREAMLY
Contagious
Low Infectious dose
Contagious for 3
days after symptoms
disappear
Norovirus
Implicated Foods
RTE
Shellfish contaminated by sewage
AKA – “Cruise Ship Poisoning”
Resistant to Chlorine Sanitizers
Prevention
Good Personal Hygiene
Exclude all infected workers
NO raw shellfish
Purchase from reputable suppliers
Parasites
Living Organisms
Require host to survive
Larger than Bacteria
Often still require microscope
Trichinella spiralis
Illness: Trichinosis
Food of concern – Pork
Habitat – Swine, boar, wild boar, marine
mammals, fox
Prevention
Cooking - 145°F
Freezing 5°F for 30 days
Curing/Salting/Smoking
Irradiation
Purchase Pork from approved sources
Avoid Cross-contamination with
other meats and grinders
Anisakis simplex
Disease: Anisakiasis
Fish Parasite
Nematode – Round worm
Fish and Squid – Bottom feeders
Marine – Salt Water
Implicated foods – Raw/undercooked fish
Sushi
--Pacific salmon
Ceviche
--Cod
Sashimi
Pickled Herring