Lecture 4 and 5: Control of Microorganisms (Sterilization and Disinfection)

Question 1

____: The absolute killing or removal of all microorganisms, including: BACTERIAL SPORES, on inanimate objects
a. Sterilization
b. Disinfection
c. Sanitation

Answer 1

a. Sterilization

Question 2

Autoclave can allow for:
a. Sterilization
b. Disinfection
c. Sanitation

Answer 2

a. Sterilization

Question 3

True or False: Sterilization destroys all bacterial products (e.g LPS/Endotoxin)

Answer 3

False - sterilization does NOT destroy all bacterial products

Question 4

True or False: Sterility does not necessarily remove or destroy microbial products

Answer 4

True

Question 5

True or False: -cidal is irreversible killer or killing while -static causes halted growth

Answer 5

True

Question 6

True or False: In -static agents, growth is halted, but when the agent is removed, microorganisms can grow

Answer 6

True

Question 7

True or False: Absence of growth does not necessarily mean sterility

Answer 7

True

Question 8

____: The killing of many but not all microorganisms. A reduction in bioburden appropriate for specified use of a substance, product, surface
A. Sanitization
B. Sterilization
C. Disinfection

Answer 8

C. Disinfection

Question 9

Bleach, phenol, and boiling are examples are:
A. Sanitizations
B. Sterilizations
C. Disinfectants

Answer 9

C. Disinfectants

Question 10

For adequate disinfection, all ___ pathogens must be killed (except for ____)

Answer 10

vegetative; endospores

Question 11

True or False: Some disinfectants can be toxic to human tissues and should only be used on inanimate objects

Answer 11

True

Question 12

Which disinfectant level is effective against most or all pathogens, but not large number of spores?
A. Intermediate
B. Low
C. High

Answer 12

C. High

Question 13

Which disinfectant level is effective against mycobacteria and other vegetative spores, as well as most viruses and fungi, but NOT bacterial/fungal spores?
A. Intermediate
B. Low
C. High

Answer 13

A. Intermediate

Question 14

Which disinfectant level is effective against most vegetative bacteria, enveloped viruses, and some fungi but NOT mycobacterial or spores?
A. High level
B. Intermediate level
C. Low level

Answer 14

C. Low level

Question 15

True or False: Disinfectant is only static

Answer 15

False - disinfectant could be cidal or static

Question 16

____: clean and no pathogens, but NOT complete disinfection and does not imply sterilization

Answer 16

Sanitization

Question 17

___: Use of heat at a temperature sufficient to kill important pathogens in liquids – usually followed by rapid chilling

Answer 17

Pasteurization

Question 18

True or False: In pasteurization, spores are killed and a liquid is sterilized

Answer 18

False
- not sterilized (some microbes are present still)
- spores are not killed

Question 19

True or False: Pasteurization is sterilization.

Answer 19

False - it is NOT sterilization - it is disinfection or preservation

Question 20

____: Chemicals used to kill microorganisms on surface of skin/mucous membranes (e.g hand sanitizer)

Answer 20

Antiseptic

Question 21

_____: procedure that involves the destruction or removal or contaminants

Answer 21

Decontamination

Question 22

Strongest degree of killing is ____, while weakest degree is ____

Answer 22

strongest = sterilization
weakest = antispetic

Question 23

True or False: Sterilization kills everything in addition to spores

Answer 23

True

Question 24

Which type of bacteria is a standard in disinfection?

Answer 24

mycobacteria

Question 25

True or False: Infectious diseases, spoilage, contamination, is often determined by numbers of microorganims present

Answer 25

True

Question 26

What two factors affect killing of microorganisms?

Answer 26

1) Application time
2) Number of organisms

Question 27

Generally, is more/less application time better?

Answer 27

More

Question 28

Generally, if the concentration of the agent is increased, the length of time needed to kill the organisms will decreased. ____ is the exception.

Answer 28

Alcohol

Question 29

If ___ is diluted by 1/2, kill time increases by 64x

Answer 29

Phenol

Question 30

For every 10 Celcius increase in temperature, chemical activity doubles while killing and inhibition time ___

Answer 30

decreases

Question 31

True or False: Chlorine activity is reduced by organic material while glutaraldehyde activity is only slightly reduced by organic material

Answer 31

True

Question 32

True or False: Iodine is both corrosive and toxic

Answer 32

True

Question 33

Surgical instruments, urinary catheters, and IV fluids are
A. Non-critical items
B. Semi-critical items
C. Critical items

Answer 33

C. Critical items
- They enter sterile tissue or blood stream

Question 34

Semi-critical items are those that come into contact with broken skin or mucus membranes. They require treatments with disinfectants that have ___ level of activity
A. Low
B. Intermediate
C. High

Answer 34

C. High level of activity

Question 35

True or False: Endospores, mycobacteria/bacteria, fungi, and viruses may be seen on semi critical items

Answer 35

True

Question 36

Non-critical items may be cleaned and treated with ____ disinfectant since they are only in contact with intact skin
A. Low level
B. Intermediate level
C. High level

Answer 36

A. Low level

Question 37

What are the three major factors that affect the efficacy of sterilization and disinfection?

Answer 37

1) Characteristics of target organisms
2) # of organisms
3) Physical features

Question 38

True or False: Hand hygiene is the single most effective means of preventing the spread of infections

Answer 38

True