Microbiological Guidelines for Food Microbiological Guidelines for ...
Chapter 4 Microbiological Contaminants
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Transcript of Chapter 4 Microbiological Contaminants
Chapter 4 Microbiological Contaminants
Chapter 4 Microbiological Contaminants
Waterworks OperationsWQT 111
Lecture 4
Waterworks OperationsWQT 111
Lecture 4
E. coli are bad?E. coli are bad?
True
False
50%50%
1. True
2. False
1. True
2. False
ObjectivesObjectives
1.Compare virus (small), bacteria (medium), and protozoa (large)
2.Review Total Coliform Rule.
3.Go Over Total Coliform Analytical Procedures.
4.Perform Colilert Test of Unknown sample.
1.Compare virus (small), bacteria (medium), and protozoa (large)
2.Review Total Coliform Rule.
3.Go Over Total Coliform Analytical Procedures.
4.Perform Colilert Test of Unknown sample.
VirusesViruses1. Smallest living entities 10 - 25 nm . Viruses can be observed only with the aid of
an electron microscope.
2. Viruses are obligate intracellular parasites - they cannot live or multiply outside of a host cell.
3. More resistant to chlorine relative to bacteria
4. Viruses are not cellular organisms. Many consist of a protein coat or capsid and internal nucleic acid, either DNA or RNA.
5. Viruses do not produce enzymes for metabolism.
6. In the process of multiplying, viruses kill the infected host cells. Important viral waterborne infections include hepatitis A and gastroenteritis (norwalk and rotavirus)
1. Smallest living entities 10 - 25 nm . Viruses can be observed only with the aid of an electron microscope.
2. Viruses are obligate intracellular parasites - they cannot live or multiply outside of a host cell.
3. More resistant to chlorine relative to bacteria
4. Viruses are not cellular organisms. Many consist of a protein coat or capsid and internal nucleic acid, either DNA or RNA.
5. Viruses do not produce enzymes for metabolism.
6. In the process of multiplying, viruses kill the infected host cells. Important viral waterborne infections include hepatitis A and gastroenteritis (norwalk and rotavirus)
You can see a virus with the naked eye?
You can see a virus with the naked eye?
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2. False
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2. False
Viruses need a host?Viruses need a host?
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Fal
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0%0%1. True
2. False
1. True
2. False
In the processes of viral metabolism enzymes are exuded
which attack the host cell?
In the processes of viral metabolism enzymes are exuded
which attack the host cell?
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2. False
1. True
2. False
Viruses are the smallest cellular organisms with a true nucleus?Viruses are the smallest cellular organisms with a true nucleus?
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1. True
2. False
1. True
2. False
BacteriaBacteria1. Smallest cellular organisms. A typical bacterium is about 1 micrometer
in size. Bacteria have a unique cell construction that sets them apart from all other living organisms.
2. The vast majority of bacteria are free living soil and water microorganisms.
3. Bacteria can exist in conditions that no other living organism can tolerate. Conan the bacterium
4. Bacteria cause many diseases in animals and man. Important waterborne infectious diseases include campylobacterosis, legionnaires disease, shigellosis, typhoid, enterovirulent E. coli 0157, and cholera.
1. Smallest cellular organisms. A typical bacterium is about 1 micrometer in size. Bacteria have a unique cell construction that sets them apart from all other living organisms.
2. The vast majority of bacteria are free living soil and water microorganisms.
3. Bacteria can exist in conditions that no other living organism can tolerate. Conan the bacterium
4. Bacteria cause many diseases in animals and man. Important waterborne infectious diseases include campylobacterosis, legionnaires disease, shigellosis, typhoid, enterovirulent E. coli 0157, and cholera.
E. coli E. coli
•E.coli are rod shaped, facultative anaerobic, gram-negative bacillus •Waste processing, Vitamin B and K production, and food absorption •They are indicators of fecal coliform
10 billion-100 trillion per day per person
•E.coli are rod shaped, facultative anaerobic, gram-negative bacillus •Waste processing, Vitamin B and K production, and food absorption •They are indicators of fecal coliform
10 billion-100 trillion per day per person
http://www.onr.navy.mil/media/view_image.asp?ID=63&SubID=64http://www.onr.navy.mil/media/view_image.asp?ID=63&SubID=64
http://pathport.vbi.vt.edu/pathinfo/pathogens/E.coli_O157H7.htmlhttp://pathport.vbi.vt.edu/pathinfo/pathogens/E.coli_O157H7.html
E. coli are necessary for human survival?
E. coli are necessary for human survival?
Tru
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0%0%
1. True
2. False
1. True
2. False
E.coli are rod shaped, facultative anaerobic, gram-negative
bacillus?
E.coli are rod shaped, facultative anaerobic, gram-negative
bacillus?
Tru
e
Fal
se
0%0%1. True
2. False
1. True
2. False
Escherichia coli type 0157:H7 (bacteria, enteric pathogen)
Escherichia coli type 0157:H7 (bacteria, enteric pathogen)
•The illness is characterized by severe cramping (abdominal pain) and diarrhea which is initially watery but becomes grossly bloody. Occasionally vomiting occurs.
•Fever is either low-grade or absent.
•The illness is usually self-limited and lasts for an average of 8 days. Some individuals exhibit watery diarrhea only.
• Infectious dose is a few as 10 bacteria cells.
•The illness is characterized by severe cramping (abdominal pain) and diarrhea which is initially watery but becomes grossly bloody. Occasionally vomiting occurs.
•Fever is either low-grade or absent.
•The illness is usually self-limited and lasts for an average of 8 days. Some individuals exhibit watery diarrhea only.
• Infectious dose is a few as 10 bacteria cells.
http://en.wikipedia.org/wiki/2006_United_States_E._coli_outbreak
"E Coli H0157" is the bacterium that is the best known
serotype of "Enterohemorrhagic E. Coli" and known by its more formal scientific name of Escherichia coli
0157:H7. Transmitted from undercooked hamburger meat and raw milk, it releases verotoxin, which causes inflammation of the lower gastrointestinal tract, often
resulting in bloody bowel movements, potentially
several other illnesses and/or death.
"E Coli H0157" is the bacterium that is the best known
serotype of "Enterohemorrhagic E. Coli" and known by its more formal scientific name of Escherichia coli
0157:H7. Transmitted from undercooked hamburger meat and raw milk, it releases verotoxin, which causes inflammation of the lower gastrointestinal tract, often
resulting in bloody bowel movements, potentially
several other illnesses and/or death.
Tru
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Fal
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0%0%1. True
2. False
1. True
2. False
BacteriaBacteria
BacteriaBacteria
coccuscoccus rodrod spirillumspirillum
Most total coliforms are rod shaped?
Most total coliforms are rod shaped?
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Fal
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0%0%1. True
2. False
1. True
2. False
ProtozoaProtozoa1. Protozoa are mostly single celled organisms that have a complex cell
construction (5-100 m).
2. Protozoa are classified into groups according to their method of motility:
• flagellates, move with the aid of one or more whip-like flagella.
• ciliates, move with the aid of a group of short hair-like cilia.
• amoeba, move with the aid of temporary cell projections called pseudopods (false feet).
3. Most protozoa are free living water and soil microorganisms.
4. Protozoa produce important diseases in animals and man. Important waterborne diseases include giardiasis, cryptosporidiosis and amoebic dysentery.
1. Protozoa are mostly single celled organisms that have a complex cell construction (5-100 m).
2. Protozoa are classified into groups according to their method of motility:
• flagellates, move with the aid of one or more whip-like flagella.
• ciliates, move with the aid of a group of short hair-like cilia.
• amoeba, move with the aid of temporary cell projections called pseudopods (false feet).
3. Most protozoa are free living water and soil microorganisms.
4. Protozoa produce important diseases in animals and man. Important waterborne diseases include giardiasis, cryptosporidiosis and amoebic dysentery.
Protozoa like to eat bacteria?Protozoa like to eat bacteria?
Tru
e
Fal
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0%0%1. True
2. False
1. True
2. False
A cilia is a whip like tail structure in a protozoa?
A cilia is a whip like tail structure in a protozoa?
Tru
e
Fal
se
0%0%1. True
2. False
1. True
2. False
Protozoa Intestinal Parasites & Water Borne Diseases
Giardia lamblia
Cryptosporidium parvum
Protozoa Intestinal Parasites & Water Borne Diseases
Giardia lamblia
Cryptosporidium parvum
Giardiasis (intestinal parasite)Giardiasis (intestinal parasite)
http://www.cfsan.fda.gov/~mow/chap22.html
•Giardia lamblia (intestinalis) is a single celled animal, i.e., a protozoa, that moves with the aid of five flagella.
•Giardia found in domestic animals (dogs and cats) and wild animals (beavers, ducks, and bears)
•Most frequent cause of non-bacterial diarrhea in North America. ~ 25% of the cases of gastrointestinal disease
•Giardiasis is most frequently associated with the consumption of contaminated water . 2% of US population. Oregon second most reported cases 1980s
•Ingestion of one or more cysts may cause disease
•Illness lasts for 1 to 2 weeks (chronic infections can last months to years). Treat with Flagyl=antibiotic
•Giardia lamblia (intestinalis) is a single celled animal, i.e., a protozoa, that moves with the aid of five flagella.
•Giardia found in domestic animals (dogs and cats) and wild animals (beavers, ducks, and bears)
•Most frequent cause of non-bacterial diarrhea in North America. ~ 25% of the cases of gastrointestinal disease
•Giardiasis is most frequently associated with the consumption of contaminated water . 2% of US population. Oregon second most reported cases 1980s
•Ingestion of one or more cysts may cause disease
•Illness lasts for 1 to 2 weeks (chronic infections can last months to years). Treat with Flagyl=antibiotic
Giardia lamblia is a bacteria that causes waterborne infection?
Giardia lamblia is a bacteria that causes waterborne infection?
Tru
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Fal
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0%0%
1. True
2. False
1. True
2. False
Giardia is found in domestic animals (dogs and cats) and wild
animals (beavers, ducks, and bears)?
Giardia is found in domestic animals (dogs and cats) and wild
animals (beavers, ducks, and bears)?
Tru
e
Fal
se
0%0%1. True
2. False
1. True
2. False
Ingestion of one or more giardia cysts may cause disease?
Ingestion of one or more giardia cysts may cause disease?
Tru
e
Fal
se
0%0%1. True
2. False
1. True
2. False
Giardia is the most frequent cause of non-bacterial diarrhea
in North America?
Giardia is the most frequent cause of non-bacterial diarrhea
in North America?
Tru
e
Fal
se
0%0%1. True
2. False
1. True
2. False
Giardia Lamblia/ProtozoaGiardia Lamblia/Protozoa
Cryptosporidiosis (protozoa) Cryptosporidiosis (protozoa) •Cryptosporidium parvum, a single-celled animal, i.e., a protozoa, is an obligate intracellular parasite.
•Infects many herd animals (cows, goats, sheep among domesticated animals, deer and elk among wild animals)
•The infective stage (oocyst) is 3 µm in diameter or about half the size of a red blood cell.
•Severe watery diarrhea lasting 2-4 days (no reliable treatment for cryptosporidiosis) •Serological surveys indicate that 80% of the population has had cryptosporidiosis.
•Cryptosporidium parvum, a single-celled animal, i.e., a protozoa, is an obligate intracellular parasite.
•Infects many herd animals (cows, goats, sheep among domesticated animals, deer and elk among wild animals)
•The infective stage (oocyst) is 3 µm in diameter or about half the size of a red blood cell.
•Severe watery diarrhea lasting 2-4 days (no reliable treatment for cryptosporidiosis) •Serological surveys indicate that 80% of the population has had cryptosporidiosis.
http://www.cfsan.fda.gov/~mow/chap24.html
CryptosporidiosisCryptosporidiosis
http://www.cfsan.fda.gov/~mow/chap24.html
•The new “superbug” Cryptosporidium parvum is first identified as an important waterborne infection in the 1990's.
•Resistant to chlorination
•Oregon reports waterborne outbreaks in 1992 Talent Oregon communities.
•1993 largest waterborne disease outbreak in US ~400,000 Milwaukee Wisconsin
•The new “superbug” Cryptosporidium parvum is first identified as an important waterborne infection in the 1990's.
•Resistant to chlorination
•Oregon reports waterborne outbreaks in 1992 Talent Oregon communities.
•1993 largest waterborne disease outbreak in US ~400,000 Milwaukee Wisconsin
Cryptosporidium/ProtozoaCryptosporidium/Protozoa
Total Coliform RuleTotal Coliform Rule• Total Coliform Rule (TCR) on June 29, 1989 • monitor for total coliforms at a frequency proportional to the number of
people served • Further test that culture for the presence of either fecal coliforms or
Escherichia coli;• Take samples at end of distribution systems• If positive occurs:
– Re-collect and analyze at least 3-4 repeat samples within 24 hours : – 1 at the same tap as the positive – The others at sites located within 5 or fewer service connection
adjacent (upstream and downstream) to the location of the routine positive sample; and
• Take at least 5 routine samples the next month of operation. • 16 different species of Total Coliforms!
• Total Coliform Rule (TCR) on June 29, 1989 • monitor for total coliforms at a frequency proportional to the number of
people served • Further test that culture for the presence of either fecal coliforms or
Escherichia coli;• Take samples at end of distribution systems• If positive occurs:
– Re-collect and analyze at least 3-4 repeat samples within 24 hours : – 1 at the same tap as the positive – The others at sites located within 5 or fewer service connection
adjacent (upstream and downstream) to the location of the routine positive sample; and
• Take at least 5 routine samples the next month of operation. • 16 different species of Total Coliforms!
EPA APPROVED METHODSTotal Coliforms
EPA APPROVED METHODSTotal Coliforms
• Presence–absence (P-A) The P-A test is a qualitative procedure that was developed as a sensitive, economical, and efficient means of analyzing drinking water samples
• Membrane filter (MF) The MF procedure was introduced to bacteriological water analysis in 1951, after its capacity to produce results equivalent to those obtained by the MTF procedure was demonstrated
• Multiple tube fermentation (MTF) procedures - The MTF procedure, in comparison with the MF procedure, lacks precision, is more difficult to perform, and takes longer to produce results; because of this, the latter has largely replaced it for routine examinations of drinking water.
• Presence–absence (P-A) The P-A test is a qualitative procedure that was developed as a sensitive, economical, and efficient means of analyzing drinking water samples
• Membrane filter (MF) The MF procedure was introduced to bacteriological water analysis in 1951, after its capacity to produce results equivalent to those obtained by the MTF procedure was demonstrated
• Multiple tube fermentation (MTF) procedures - The MTF procedure, in comparison with the MF procedure, lacks precision, is more difficult to perform, and takes longer to produce results; because of this, the latter has largely replaced it for routine examinations of drinking water.
Presence/AbsencePresence/Absence
• Incubate tubes or bottles • YES OR NO?• Fluorescent end product from E.Coli
fermentation
• Incubate tubes or bottles • YES OR NO?• Fluorescent end product from E.Coli
fermentation
PositiveE.Coli
What is the most common method used in labs to test for
total coliform and E. coli?
What is the most common method used in labs to test for
total coliform and E. coli?
DM
A
Gre
en
Colil
ert
Lam
p
0% 0%0%0%
1. DMA
2. Green
3. Colilert
4. Lamp
1. DMA
2. Green
3. Colilert
4. Lamp
Total ColiformsTotal Coliforms
Total Coliforms (m-Endo broth)Total Coliforms (m-Endo broth)
Total ColiformTotal Coliform
• Red colony with a metallic sheen within 24±2 hours at 35±0.2oC
• Red colony with a metallic sheen within 24±2 hours at 35±0.2oC
Total Coliforms (http://dl.clackamas.cc.or.us/wqt111/unit-8-coliformtest.htm)Total Coliforms (http://dl.clackamas.cc.or.us/wqt111/unit-8-coliformtest.htm)
Membrane FiltrationMembrane Filtration
Fecal Coliforms (m-FC broth)Fecal Coliforms (m-FC broth)• Blue colonies for fecal
coliforms. Gray to cream colored are non fecal coliforms
• Blue colonies for fecal coliforms. Gray to cream colored are non fecal coliforms
Fecal Coliform
Fecal Coliform
• Blue colony within 24±2 hours at 44.5±0.5oC
• Blue colony within 24±2 hours at 44.5±0.5oC
MI-Media: Pure Culture of Escherichia coli ATCC 25922 with UV Light (http://www.whatman.com/products/?pageID=7.61.409.297)
MI-Media: Pure Culture of Escherichia coli ATCC 25922 with UV Light (http://www.whatman.com/products/?pageID=7.61.409.297)
Fecal Coliforms (http://dl.clackamas.cc.or.us/wqt111/unit-8-coliformtest.htm)Fecal Coliforms (http://dl.clackamas.cc.or.us/wqt111/unit-8-coliformtest.htm)
In the membrane filter method, the number of coliforms is
estimated by the:
In the membrane filter method, the number of coliforms is
estimated by the:
Num
ber o
f col
onies
...
Num
ber o
f neg
ativ
e t..
.
Num
ber o
f pos
itive
t...
Sum
of p
ositiv
e an
d ...
0% 0%0%0%
1. Number of colonies grown
2. Number of negative tubes
3. Number of positive tubes
4. Sum of positive and negative tubes
1. Number of colonies grown
2. Number of negative tubes
3. Number of positive tubes
4. Sum of positive and negative tubes
Fecal Coliforms are incubated at 44.5oC for 24 hours
Fecal Coliforms are incubated at 44.5oC for 24 hours
Tru
e
Fal
se
0%0%1. True
2. False
1. True
2. False
When conducting the fecal coliform membrane test, count
all the colonies that are _______ in color.
When conducting the fecal coliform membrane test, count
all the colonies that are _______ in color.
Red
Yel
low
Blu
e
Ora
nge
0% 0%0%0%
1. Red
2. Yellow
3. Blue
4. Orange
1. Red
2. Yellow
3. Blue
4. Orange
Fecal coliforms are incubated in a water bath at this temperature
for 24 hours.
Fecal coliforms are incubated in a water bath at this temperature
for 24 hours.
44.
5 oC
35.
0 oC
103
oC
37.
5 oC
0% 0%0%0%
1. 44.5 oC
2. 35.0 oC
3. 103 oC
4. 37.5 oC
1. 44.5 oC
2. 35.0 oC
3. 103 oC
4. 37.5 oC
The recommended holding time for a fecal coliform sample prior to analysis is 24 hours or less at
4 deg. C.?
The recommended holding time for a fecal coliform sample prior to analysis is 24 hours or less at
4 deg. C.?
Tru
e
Fal
se
0%0%1. True
2. False
1. True
2. False
Multiple Tube Fermentation MethodMultiple Tube Fermentation MethodInoculate lauryl tryptose broth and incubate for 24h at 35oCInoculate lauryl tryptose broth and incubate for 24h at 35oC
Gas or acidityTransfer to BGBB
incubate 48 h at 35oC
Gas or acidityTransfer to BGBB
incubate 48 h at 35oC
No gas or acidityIncubate
24 h at 35oC
No gas or acidityIncubate
24 h at 35oC
Gas produced Coliform group confirmed
Gas produced Coliform group confirmed
No gas produced - test. Coliform group absent
No gas produced - test. Coliform group absent
Gas produced Confirm as in (1)
Gas produced Confirm as in (1)
Acidic growth produced Confirm as in (1)
Acidic growth produced Confirm as in (1)
No gas or acidic growth produced -test.Coliformgroup absent
No gas or acidic growth produced -test.Coliformgroup absent
Re-inoculate in fresh BGBBPositive completed phase
Re-inoculate in fresh BGBBPositive completed phase
Multiple Tube Fermentation MethodMultiple Tube Fermentation Method
• Step 1 presumptive phase• Use lauryl tryptose broth• Grow “stressed” organisms• Confirm positives• Calculate MPN
• Step 1 presumptive phase• Use lauryl tryptose broth• Grow “stressed” organisms• Confirm positives• Calculate MPN
GrowthGrowth
GasGas
http://www.bact.wisc.edu/Microtextbook/index.php?module=Book&func=displaychapter&chap_id=55&theme=printer
Habitats of Fecal and NonFecal Coliforms
Habitats of Fecal and NonFecal Coliforms
There are 16 different species of coliforms in nature?
There are 16 different species of coliforms in nature?
Tru
e
Fal
se
0%0%
1. True
2. False
1. True
2. False
E. coli results must always be higher or lower than fecal
coliform results?
E. coli results must always be higher or lower than fecal
coliform results?
Hig
her
Lower
0%0%
1. Higher
2. Lower
1. Higher
2. Lower
What is an IDEAL INDICATOR? What is an IDEAL INDICATOR?
• Be applicable in all water types.• ALWAYS be present in water when
pathogenic bacteria of fecal contamination are present. – Density or numbers should relate to
amount/degree of pollution– Greater survival time in water– Disappears rapidly following the
disappearance of pathogens
• Be applicable in all water types.• ALWAYS be present in water when
pathogenic bacteria of fecal contamination are present. – Density or numbers should relate to
amount/degree of pollution– Greater survival time in water– Disappears rapidly following the
disappearance of pathogens
Coliform bacteria- Microorganisms predominantly inhabiting the intestines of humans and other animals, but also occasionally found elsewhere. They include all aerobic and facultative anaerobic, Gram-negative, nonspore-forming, rod-shaped bacteria that ferment lactose with the production of gas. Also included are all bacteria that produce a dark, purplish-green metallic sheen by the membrane filter technique used for coliform identification.
Coliform bacteria- Microorganisms predominantly inhabiting the intestines of humans and other animals, but also occasionally found elsewhere. They include all aerobic and facultative anaerobic, Gram-negative, nonspore-forming, rod-shaped bacteria that ferment lactose with the production of gas. Also included are all bacteria that produce a dark, purplish-green metallic sheen by the membrane filter technique used for coliform identification.
Tru
e
Fal
se
0%0%1. True
2. False
1. True
2. False
What is an IDEAL INDICATOR? What is an IDEAL INDICATOR?
– Absent from a bacteriologically safe water– Easily analyzed for without any anomalies
or false positives. – Greater survival time in water– Disappears rapidly following the
disappearance of pathogens– Be harmless to man or other animals
– Absent from a bacteriologically safe water– Easily analyzed for without any anomalies
or false positives. – Greater survival time in water– Disappears rapidly following the
disappearance of pathogens– Be harmless to man or other animals
Total and fecal coliform are all pathogenic?
Total and fecal coliform are all pathogenic?
Tru
e
Fal
se
0%0%1. True
2. False
1. True
2. False
Coliform bacteria are:Coliform bacteria are:
More
resi
stan
t...
Les
s re
sist
ant..
.
A g
roup o
f pat
...
A g
roup o
f pat
...
0% 0%0%0%
1. More resistant to chlorination than pathogenic bacteria
2. Less resistant to chlorination than pathogenic bacteria
3. A group of pathogens causing hepatitis
4. A group of pathogens causing cholera
1. More resistant to chlorination than pathogenic bacteria
2. Less resistant to chlorination than pathogenic bacteria
3. A group of pathogens causing hepatitis
4. A group of pathogens causing cholera
Which of the following are true about indicator organisms?
Which of the following are true about indicator organisms?
Be
prese
nt whe.
..
Be
at lo
wer
nu...
Hav
e a
shorte
r...
Be
able
to k
il...
0% 0%0%0%
1. Be present when pathogen is present
2. Be at lower numbers then the pathogen
3. Have a shorter lifespan then a pathogen
4. Be able to kill a pathogen and a lab technician in the same day
1. Be present when pathogen is present
2. Be at lower numbers then the pathogen
3. Have a shorter lifespan then a pathogen
4. Be able to kill a pathogen and a lab technician in the same day
Fecal coliforms are a subset of total coliform bacteria?
Fecal coliforms are a subset of total coliform bacteria?
Tru
e
Fal
se
0%0%1. True
2. False
1. True
2. False
Coliforms are used as indicator bacteria to verify the effectiveness of disinfection
techniques because ______.
Coliforms are used as indicator bacteria to verify the effectiveness of disinfection
techniques because ______.
They
are
the
m...
They
cau
se th
e...
They
are
eas
ie...
They
hav
e a
sy...
0% 0%0%0%
1. They are the most numerous of all wastewater pathogens
2. They cause the worst diseases of any of the wastewater pathogens
3. They are easier to detect and are harder to destroy than most pathogenic organisms
4. They have a symbiotic relationship with pathogens; one cannot survive without the other.
1. They are the most numerous of all wastewater pathogens
2. They cause the worst diseases of any of the wastewater pathogens
3. They are easier to detect and are harder to destroy than most pathogenic organisms
4. They have a symbiotic relationship with pathogens; one cannot survive without the other.
Coliform bacteria are:?Coliform bacteria are:?
Com
monly
foun
d...
Des
irable
in s
...
Hig
hly re
sist
a...
Indi
cato
r org
a...
Dea
dly
0% 0% 0%0%0%
1. Commonly found throughout distribution systems
2. Desirable in storage tanks for iron digestion
3. Highly resistant to chlorine
4. Indicator organisms
5. Deadly
1. Commonly found throughout distribution systems
2. Desirable in storage tanks for iron digestion
3. Highly resistant to chlorine
4. Indicator organisms
5. Deadly
A
com
paris
on o
...
Indi
cato
r org
a...
An in
dicat
or o
...
All
of the
abo...
0% 0%0%0%
# of organisms# of organisms
TimeTime1. A comparison of pathogens to indicator
organism
2. Indicator organisms should outlive a pathogen
3. An indicator organism can coexist with a pathogen
4. All of the above
1. A comparison of pathogens to indicator organism
2. Indicator organisms should outlive a pathogen
3. An indicator organism can coexist with a pathogen
4. All of the above
..
This is the special sugar that fecal coliform bacteria can
metabolize.
This is the special sugar that fecal coliform bacteria can
metabolize.
Glu
cose
Fru
ctose
Lac
tose
Rosa
lic a
cid
0% 0%0%0%
1. Glucose
2. Fructose
3. Lactose
4. Rosalic acid
1. Glucose
2. Fructose
3. Lactose
4. Rosalic acid
Coliform bacteria and the procedures used to test for them
are divided into the two categories of _______.
Coliform bacteria and the procedures used to test for them
are divided into the two categories of _______.
MF a
nd M
TF
LTB a
nd BG
B
Tota
l and
feca
...
M-E
ndo a
nd M-F
...
0% 0%0%0%
1. MF and MTF
2. LTB and BGB
3. Total and fecal coliforms
4. M-Endo and M-FC
1. MF and MTF
2. LTB and BGB
3. Total and fecal coliforms
4. M-Endo and M-FC
Objective #4 on the syllabus (Understand the fundamentals of water microbiology,
especially as it relates to waterborne infectious disease) has been met?
Objective #4 on the syllabus (Understand the fundamentals of water microbiology,
especially as it relates to waterborne infectious disease) has been met?
Stro
ngly A
gree
Agre
e
Dis
agre
e
Stro
ngly D
isag
ree
60%
0%0%
40%1. Strongly Agree
2. Agree
3. Disagree
4. Strongly Disagree
1. Strongly Agree
2. Agree
3. Disagree
4. Strongly Disagree