week 4- food and water safety f2011student
TRANSCRIPT
-
8/3/2019 Week 4- Food and Water Safety f2011student
1/35
Food and Water Safety
Definitions
Food borne Infections
- Ingestion of ________ microorganisms
- __________ incubation times
Food borne Microbial Intoxication
- Food contains the active toxin
- Incubation time 24 to 48 hours
-
8/3/2019 Week 4- Food and Water Safety f2011student
2/35
Water Contaminants
Physical contaminants
Presence of particulate matter
Chemical contaminants
Industrial activities or agricultural runoff
-
8/3/2019 Week 4- Food and Water Safety f2011student
3/35
Biological contaminants
Overabundance of organisms or presence
of non-native microorganisms
-
8/3/2019 Week 4- Food and Water Safety f2011student
4/35
CDC Risk- The Top Five
Shigella dysenteriae
Escherichia coliO157:H7 (E. coli)
Salmonella species Vibrio cholerae
Cryptosporidium parvum (C. parvum)
-
8/3/2019 Week 4- Food and Water Safety f2011student
5/35
Other,
- Norwalk virus, Hepatitis A and hepatitis E
- Helmiths or worms such as tapeworms,
flukes and round worms
- Fungi and molds
-
8/3/2019 Week 4- Food and Water Safety f2011student
6/35
Shigella dysenteriae
One of four types of __________ bacteria that
produces a diarrhea inducing, disease causing
enterotoxin
All four strains cause dysentery (shigellosis)
S. dysenteriae, S. flexneri, S. boydii, S. sonnei
200 cells could cause infection as little affected by
stomach acids
-
8/3/2019 Week 4- Food and Water Safety f2011student
7/35
-
8/3/2019 Week 4- Food and Water Safety f2011student
8/35
S. Dysenteriae
Secretes an exotoxin, Shiga toxin, stops protein
synthesis in its hosts cells
Pathophysiology
-
8/3/2019 Week 4- Food and Water Safety f2011student
9/35
-
8/3/2019 Week 4- Food and Water Safety f2011student
10/35
E. Coli 0157:H7
Gram negative rod shaped bacteria with
_____ virulence (as few as 10 organisms)
First described as a cause of human illness
in 1982
E. coli is the most common type of
pathogenic infection ___________
-
8/3/2019 Week 4- Food and Water Safety f2011student
11/35
Sources
Animal and Other Sources
- improperly composted manure- contaminated water*
- spread animal to person and person to
person, _______________
-
8/3/2019 Week 4- Food and Water Safety f2011student
12/35
Food Sources
- undercooked beef- Non pasteurized milk and cheese
- spinach and other fruits and/or vegetables
contaminated with feces
-
8/3/2019 Week 4- Food and Water Safety f2011student
13/35
Pathophysiology ofE.coli0157:H7
Introduces two types of cells into intestinal
cells
Proteins of one type disrupt cell
metabolism
Proteins of another type lodge in cell
cytoplasm and enables this strain to
displace others
-
8/3/2019 Week 4- Food and Water Safety f2011student
14/35
Produces _________ inhibits protein
synthesis, attaches to neutrophil surfaces
and is spread in body widespread
death of host cells and tissue
Antimicrobial drugs __________
production ofShiga-like toxin
-
8/3/2019 Week 4- Food and Water Safety f2011student
15/35
S/S
Some show minimal, or no illness, and
become carriers
bloody or watery diarrhea, cramping,
nausea and vomiting
-
8/3/2019 Week 4- Food and Water Safety f2011student
16/35
Some may develop hemolytic uremic syndrome
(HUS)
Destruction of red blood cells and kidney failure
3-5% mortality
http://www.idph.state.il.us/Bioterrorism/factsheets/food_water_b
http://www.idph.state.il.us/Bioterrorism/factsheets/food_water_borne.htmhttp://www.idph.state.il.us/Bioterrorism/factsheets/food_water_borne.htm -
8/3/2019 Week 4- Food and Water Safety f2011student
17/35
Vibrio cholerae
The only cholerae species that can survive
in fresh water
Strain 01 El Tor has caused pandemics
Strain 0139 Bengal arose in India in 1992
May be destroyed by stomach acid so size
of infectious dose 108 cells
-
8/3/2019 Week 4- Food and Water Safety f2011student
18/35
Pathophysiology
Cholera toxin enters epithelial cells liningintestine causing loss of sodium andchloride with water following the
electrolytes causing __________
-
8/3/2019 Week 4- Food and Water Safety f2011student
19/35
Oral Rehydration Therapy
Developed by WHO
Fluid/electrolyte replacement with sodium
______________________________________
dissolved in water (similar to Pedialyte)
-
8/3/2019 Week 4- Food and Water Safety f2011student
20/35
Clostridium Botulism
Spore forming anaerobe in water and soil
and, occasionally, animal intestinal tract
Human and animal distinctly different
types
Botulin is the most potent microbial toxin
known to mankind
-
8/3/2019 Week 4- Food and Water Safety f2011student
21/35
Food Sources of Botulism
Spores are present on vegetables or meat at
time of gathering
Reasons for Spread
________ cooking does not reach
sufficient pressure or temperature to kill
-
8/3/2019 Week 4- Food and Water Safety f2011student
22/35
Processing removes oxygen encouraging
growth
Room temperature storage favors spore
germination and growth
-
8/3/2019 Week 4- Food and Water Safety f2011student
23/35
Pathophysiology and S/S
Botulin prevents the uptake of theneurotransmitter substance acetylcholineat the neuromuscular junction
Muscles of head- double vision, difficulty inswallowing but no cognitive lapse
Causes descending muscular paralysis andrespiratory compromise with death fromrespiratory failure
-
8/3/2019 Week 4- Food and Water Safety f2011student
24/35
Norwalk Virus (Norwalk, Ohio)
Cup-shaped enteric virus transferred
orofecally from human to human
Reservoir is _______
camps, day care, cruise ship, nursing home
Gastroenteritis- acute onset with N/V,
cramps, diarrhea, and chills recovery
-
8/3/2019 Week 4- Food and Water Safety f2011student
25/35
Hepatitis
Viral infections of liver necrosis of
hepatocytes and liver inflammation
S/S may include jaundice, malaise, fever,
chills, diarrhea, abdominal pain, and
blood abnormalities
Outcome is recovery to risk of,..
-
8/3/2019 Week 4- Food and Water Safety f2011student
26/35
Food Safety Handling Tipshttp://www.dukehealth.org/health_library/care_guides/cancer/tre
Buy refrigerated foods that are cold and frozen
food that is solid. Shop for these last and get
them home quickly ___________________________________
Place raw meat and poultry in separate plastic
bags to prevent dripping on other foods
Wash your hands with soap and running water
before and after preparing foods
http://www.dukehealth.org/health_library/care_guides/cancer/treatment_instructions/preventing_food_and_water_borne_illnesshttp://www.dukehealth.org/health_library/care_guides/cancer/treatment_instructions/preventing_food_and_water_borne_illness -
8/3/2019 Week 4- Food and Water Safety f2011student
27/35
Cook meat and poultry to > 165F and eggs untilfirm
Put cooked meat and poultry on a clean platter
Separate raw and cooked foods to avoid crosscontamination
Be careful not to use the same cutting board formeats and vegetables
Wash all surfaces and supplies thoroughly Refrigerate leftovers promptly with maximum of
two hours
-
8/3/2019 Week 4- Food and Water Safety f2011student
28/35
Reheat leftovers to > ________
Bring soups, sauces and gravies to a rolling boil
and then simmer for ten minutes
Avoid preparing food for others if you are ill
-
8/3/2019 Week 4- Food and Water Safety f2011student
29/35
Prevention of Food Spoilage
[Thompson, Manore, Sheeshka)
Salting and sugaring
Drying
Smoking
Cooling
Industrial canning
Pasteurization
Addition of preservatives
-
8/3/2019 Week 4- Food and Water Safety f2011student
30/35
Water Contaminants
Previously done,
Vibro cholerae Shigella spp.
Salmonella spp. E. coli Norwalk Clostridium Botulism
Giardia intestinalis (lamblia)
-
8/3/2019 Week 4- Food and Water Safety f2011student
31/35
Giardia intestinalis
Pathogenic flagellate with________
Infection from flagellate ______ which cansurvive for __________ months in the
environment
-
8/3/2019 Week 4- Food and Water Safety f2011student
32/35
Reservoir
intestinal tracts of humans and animals
(beaver, coyotoes, cats,) world-wide
Water- mountain stream clean and
municipal as chlorine amounts insufficient
[ozone, iodine, boiling]
soil, feces-contaminated surfaces
-
8/3/2019 Week 4- Food and Water Safety f2011student
33/35
Pathophysiology and S/S
Cysts enter duodenum, __________ and
travel to jejunum damage to epithelium
[reversible]
Diarrhea, abdominal pain and flatulence
-
8/3/2019 Week 4- Food and Water Safety f2011student
34/35
Steps in Water Treatment
[Burton text]
Filtration- removal of large debris ie. Branches
Sedimentation- water rests in holding tank
allowing debris to settle to the bottom
Coagulation- Aluminum potassium sulfate added
to resting water to clump the debris
-
8/3/2019 Week 4- Food and Water Safety f2011student
35/35
Filtration- water passes through sand, earth filters,charcoal filters or membrane filters to removeremaining bacteria, protozoas, and others suchas C. Parvum
Chlorination- 0.2 to 1 ppm chlorine gas or othersubstance. In some facilities ozone or ultraviolet
light may be used instead
Multiple places for errors so need to check water