Infection Control/Occupational Health and Safety Flashcards
(220 cards)
1
Q
Who introduced the earliest belief that life was “spontaneously generated” from nonliving matter?
A
Aristotle
2
Q
Who used a primitive microscope to observe water and tooth scrapings, and viewed “animalcules”?
A
Antony van Leeuwenhoek
3
Q
What did John Tyndall explain?
A
the need for prolonged heating to destroy microbial life in broth
4
Q
Who discovered that bacteria existed in heat-stable/sensitive forms? What was the solution?
A
John Tyndall; intermittent heating, called tyndallization
5
Q
Who described heat-stable forms of bacteria as endospores?
A
Ferdinand Cohn
6
Q
Who reduced the risk of airborne infection during surgery by using carbolic acid?
A
Joseph Lister
7
Q
Who is Robert Koch?
A
- developed the two-part (petri) dishes used for growing bacteria
- provided techniques and discipline necessary to guide future microbiologists
8
Q
Who is the petri dish named after?
A
Julius Petri, a German bacteriologist
9
Q
Who disproved Aristotle’s idea of spontaneous generation of life?
A
Louis Pasteur
10
Q
What was the purpose of Pasteur’s swan-neck flask experiment?
A
To show that microorganisms come from the environment, not spontaneous generation. The S-shaped neck trapped dust and kept the broth sterile.
11
Q
How did Pasteur’s experiment disprove spontaneous generation?
A
The broth stayed free of microorganisms until the flask’s top was removed, proving that life does not arise spontaneously but comes from existing microbes.
12
Q
What is Koch’s Postulates?
A
A set of criteria that establishes whether bacteria is pathogenic
13
Q
What are all 4 steps of Koch’s Postulates?
A
- The microbial agent must be found in every case of disease
- The microorganism must be isolated and grown in pure culture
- The microorganism must cause the same disease when inoculated into a susceptible animal
- The same microbial agent must be recovered from the inoculated animal
14
Q
Who is the father of microbiology?
A
Louis Pasteur
15
Q
What did Louis Pasteur do for the French?
A
Saved the wine industry by understanding acid-producing bacteria in the vats of wine
16
Q
Who prepared the first rabes vaccine?
A
Louis Pasteur
17
Q
What are the five groups of microorganisms?
A
bacteria
algae
protozoa
fungi
viruses
18
Q
Which microorganism have been described as “perfect parasites” because they live inside the cells of a host and replicate quickly?
A
viruses
19
Q
What is a host cell?
A
cells in which invading viruses live and replicat
20
Q
What is the name of the recently discovered infectious particle? Why is it unique?
A
Prions; They contain abnormal proteins with no DNA or RNA.
21
Q
What are Prions responsible for?
A
A group of chronic diseases with long incubation periods.
22
Q
What temperature do pathogenic bacteria grow best at?
A
98.6F (37C)
23
Q
What are harmless, beneficial bacteria called?
A
flora
24
Q
How does bacterial infection occur? What is this known as?
A
when bacteria that are beneficial for one part of the body invade another part and become harmful, this is known as opportunistic flora
25
What are the three classifications of bacteria?
based on shape:
1. spherical (cocci)
2. rod (bacilli)
3. spiral (spirochetes)
26
What is Cocci?
spherical shaped bacteria
reproduce by dividing into two
27
What does Cocci form as they divide?
chains called streptococci
28
What are Cocci that form irregular groups or clusters called?
staphylococci
29
What is Bacilli?
rod-shaped bacteria
30
What bacteria causes tuberculosis?
Bacilli
31
What are Spirochetes?
spiral-shaped bacteria
flexible cell walls
capable of movement
32
What bacteria causes lyme disease and syphilis?
Spirochetes
33
Who is Hans Christian Gram?
Danish bacteriologist that developed a 4-step staining process for separating bacteria into 2 groups
34
What are aerobes?
a variety of bacteria that require oxygen to grow
35
What are Anaerobes?
bacteria that grow in the lack of oxygen and die in oxygen
36
What are Facultative Anaerobes?
organisms that can grow in the presence of the absence of oxygen
37
What does Streptococcus mutans (SM) have on its cell wall that protects, and shows capability to cause disease?
a capsule
38
What microorganism can transform into highly resistant spores?
bacteria
39
What is the most resistant form of life, what can it be used for?
spores; test effectiveness of sterilization techniques
40
What are Rickettsiae?
short, nonmotile rods that live in the intestines of insects
41
How do RIckettsiae spread?
require host cells to reproduce
transmitted to humans through animal bites
42
What is algae?
single cell or multicell organisms that contain chlorophyll
43
What are protozoa?
large group of one-celled organisms that do not have a rigid cell wall that eat bacteria, small algae, and protozoa
44
Why can some protozoa remain viable outside their hosts for long periods?
cysts outside their hosts for long periods because the thick walls of the cysts make them resistant to drying.
45
What are fungi?
organisms such as mushrooms, yeasts, and molds that lack chlorophyll
46
What is a common fungi in the mouth?
Candid, a yeast
47
What is Oral candidiasis?
a yeast infection that is caused by Candida albicans
48
Who is susceptible to candidiasis?
very young, very old, very ill, HIV infected patients
49
What is Oral Candidiasis characterized by?
white membranes on oral mucosa, tongue, and oral cavity
50
Who discovered Prions?
Dr. Stanley Prusiner while researching neurological disease
51
What are Prions?
small proteinaceous infectious particles
Composed of DNA or RNA
52
How did the discovery of prions change how disease was thought of?
showed that proteins can transmit disease, prior it was believed that an infectious agent was made of genetic material
53
How do Prions work?
convert normal proteins into dangerous ones by changing their shape
54
What do prions cause?
Fatal diseases, that affect the brain, known as spongiform encephalopathy
55
What does the CDC recommend to inactivate disease caused by Prions?
placing in sodium hydroxide for 2 hrs
steam sterilization at 121C for 1 hr
56
How do viruses spread?
virus invades a host cell
replicates
destroys the host cell to release
57
Why do viruses need specificity for particular cell types to replicate? Examples?
Viruses must have specificity (preference) for particular cell types to replicate because they need to attach to specific receptors on the host cells.
HIV, infect CD4 cells,
Hepatitis, infect liver cells.
58
How does HIV go from mother to infant? What's the infection rate?
Some viruses can cross the placenta and infect the fetus. One-fourth of HIV-infected mothers pass the infection to their infants.
59
What is a viral infection during pregnancy that causes intellectual disability, blindness, and impaired hearing?
cytomegalovirus (CMV)
60
What is a latent virus?
Establishes a dormant state in host cells, meaning it does not cause immediate symptoms but can be reactivated later.
61
What is a provirus?
A provirus is a virus that becomes integrated into the nucleic acid of the host cell, allowing it to remain dormant and reactivate later.
62
What is the treatment plan for viral infections?
treated symptomatically
63
What are the 6 forms of transmission for viruses?
direct contact
insects
percutaneous injury
blood transfusions
contaminated food/water
droplet inhalation
64
How can viruses be destroyed in the environment?
chemicals like bleach, iodine, phenal, and formaldehyde
65
What is Hepatitis A? How can it be stopped?
A virus that can affect anyone
fecal-oral transmission
can be prevented by proper hygiene and vaccine
66
What is the least serious form of viral hepatitis?
Hepatitus A virus (HAV)
67
What is Hepatitis B?
a very serious disease that may result in prolonged illness, liver cancer, cirrhosis, liver failure, and death
68
How is HBV spread?
bloodborne disease that can also be transmitted through other body fluids
69
What is the percentage of viral hepatitis that HBV is responsible for?
34%
70
How is Hepatitis C virus (HCV) transmitted, and is there a vaccine available?
HCV is primarily transmitted through blood transfusion or percutaneous exposure to blood.
NO VACCINE
71
Why is HCV often diagnosed late, and how does it affect the liver?
75% of people infected are unaware, allowing liver damage to progress silently
72
How has HCV treatment improved over the years?
Before 2011, treatment could take up to a year with only a 40-50% cure rate.
Advances have shorter, injection-free treatments with higher cure rates
73
What is Hepatitis D?
a defective virus that cannot replicate itself without HBV
74
What is HDV's relationship with HBV?
HDV must occur simulataneously with HBV
combined, they are more dangerous than HBV alone
75
How is HEV spread?
fecal-oral route (contaminated food or water)
76
Where is HEV usually seen?
epidemics in developing countries
77
What is HIV?
a blood-borne viral disease where the body's immune system breaks down
78
What happens during HIV?
the virus infects special T cells and slowly kills them
79
What virus causes AIDS?
HIV
80
What is herpescirus?
a double-stranded DNA virus that causes infection in humans such as herpes, CMV, chickenpox, shingles, mononucleosis, measles, and Kaposi's sarcome
81
What are the four major herpesviruses?
Herpes Simplex Virus (HSV 1 and HSV 2)
Herpes/varicella zoster virus (HZV)
Cytomegalovirus (CMV)
epstein-Barr virus (EBV)
82
What is Herpes Simplex Virus type 1?
a viral infection that causes recurrent sores on the lips also known as fever blisters or cold sores
83
Where does HSV 1 first appear?
children 1-3 years old that causes pain, increased salivation, halitosis, and swelling
84
What is the healing duration of HSV 1?
healing begins within 3 days, and lasts 7-14 days
85
After HSV 1 first appears, what happens? How can it be prevented?
lies dormant and reappears later in life when general resistance is lowered resulting in cold sores, using SPF can reduce sun-induced recurrences
86
What is the healing process of recurrent herpes sores?
7-10 days no scar
87
What is HSV 2?
genital herpes, the most common STD in the US
88
What are the symptoms of HSV 2?
2-10 days after infection symptoms of tingling, iching, and a burning sensation when urinating will appear
89
When is HSV 2 transmissable?
during the recurrences
90
If a mother is infected with HSV 2, what is the chance that a newborn is infected too?
50%
91
If a newborn is infected with HSV 2, what are the chances it will be severely damaged or killed by the virus?
85%
92
What is HZV?
human herpesvirus type 3 that causes both varicella (chickenpox) and herpes zoster (shingles)
93
How is HZV transmitted?
through direct contact with skin lesions or through droplet infection from infectious saliva
94
What portion of HZV causes varicella (chickenpox)?
the primary infection
95
What portion of HZV causes zoster(shingles)?
the reactivation of the illness
96
What is CMV?
human herpesvirus type 5 that usually doesn't cause disease but may infect the fetus causing deafness or intellectual disability
97
What diseases is EBV responsible for?
infectious mononucleosis
nasopharyngeal cancer
lymphome
oral hairy leukoplakia
98
What is EBV known as? Why?
Kissing disease: present in saliva
99
How is herpesvirus transmitted?
through direct contact with lesions or infectious saliva it can spread via saliva or aerosol spray from dental equipment
100
Is there a vaccine for herpes, and what precautions should be taken?
NO VACCINE
avoiding exposure
wearing protective eyewear
using gloves
101
What is H1N1, and how is it caused?
a respiratory disease of pigs caused by type A viruses.
102
How long can an infected person with H1N1 be contagious?
From 1 day before symptoms to 7+ days; longer in children.
103
How does H1N1 spread from one person to another?
Through droplets or touching contaminated surfaces.
104
What is Ebola, and how deadly is it?
A rare, not very contagious but deadly virus causing internal and external bleeding, with a fatality rate of up to 90%.
105
How does Ebola spread?
Through direct contact with infected blood or body fluids like urine, feces, saliva, vomit, and semen.
106
How is Zika virus transmitted?
Through the bite of an infected Aedes mosquito.
107
What are common symptoms of Zika? Duration?
Fever, rash, joint pain, and conjunctivitis (red eyes).
up to 7 days
108
What can Zika cause during pregnancy
birth defects, such as microcephaly
109
What causes tuberculosis?
The bacterium Mycobacterium tuberculosis.
110
Why is tuberculosis a high risk for healthcare workers?
It is highly infectious and resistant to disinfectants.
111
How is tuberculosis used in disinfectant testing?
Its kill time is the benchmark for surface disinfectant effectiveness.
112
What diseases does Legionella pneumophila cause?
Pontiac fever and Legionnaires’ disease.
113
Where and how is Legionella pneumophila transmitted?
through aerosolized contaminated water, like lakes, hot tubs, AC,
NOT person-to-person,
114
What diseases is Legionella pneumophila bacterium responsible for
two acute bacterial diseases:
- Pontiac Fever
- Legionnaires' Disease
115
How is Legionella pneumophila bacterium spread?
aerosolization and aspiration of contaminated water
NO PERSON TO PERSON
116
What is the more and less serious form of Legionella pneumophila bacterium?
Less serious: Pontiac Fever
More serious: Legionnaires' Disease
117
What is Tetanus caused by? How does it enter?
a spore-forming bacillus found in soil, dust, or feces
enters through a break in the skin
118
What is syphilis? Caused by?
an STD caused by Treponema Pallidum Spirochetes
119
What are the 3 stages of syphilis?
1. presence of infectious, ulcerating sore, known as a chancre (resembles herpes, but crust is darker)
2. infectious open sore
3. latent syphilis, that occurs after 20 years
120
What is MRSA, and why is it significant?
MRSA (Methicillin-resistant Staphylococcus aureus) is a type of bacteria resistant to some antibiotics, including methicillin.
121
How has MRSA developed antibiotic resistance?
It evolved due to excessive use of penicillin-type antibiotics.
122
How common is S. aureus (MSRA) in the general population?
Around 30% of people worldwide carry S. aureus without developing symptoms.
123
Where are MRSA infections most commonly found on the body?
MRSA infections can occur on the skin’s surface or deeper in the soft tissue, forming a boil or abscess.
124
What types of places are at higher risk for MRSA infections?
Places with close contact between people, such as schools, dormitories, military barracks, and daycare facilities, are at higher risk.
125
What are some key prevention tips for avoiding MRSA infections?
Maintain good hand hygiene, avoid squeezing sores, keep wounds covered, and do not share personal items like towels, razors, or clothes.
126
What are the 6 chain in "The Chain of Infection"
1. An infectious agent
2. A reservoir
3. A portal of exit
4. Mode of transmission
5. Portal of entry
6. A susceptible host
127
What is bioburden?
organic material such as blood and saliva
128
What is an infectious agent
a pathogen with sufficient number to cause infection
129
What is a reservoir? Name Examples
a place where microorganisms normally live and reproduce
humans, animals, water, food, contaminated surfaces, bioburden
130
How can you minimize the number of reservoirs in the dental setting?
using a dental dam
high-volume evacuation
excellent hand hygiene
thorough cleaning of contaminated surfaces
131
What is a portal of entry? Name examples.
a means of entering the body
airborne pathogens - mouth and nose
bloodborne pathogens - blood supply
132
What is a susceptible host?
a person who is unable to resist infection by a particular pathogen
133
What is an acute infection?
a short-duration infection with severe symptoms
134
What is a chronic infection?
where a microorganism is present for a long duration, some for life
135
What is a latent infection?
a persistent infection in which the symptoms "come and go"
136
What is an opportunistic infection?
normally non pathogenic organisms, occur in individuals whose resistance is decreased or compromised
137
What is direct transmission?
person-to-person contact
droplets
body fluids
138
What is indirect transimission
when pathogens are first transmitted to an object or surface then passed on to another person who touches them
139
What is airborne transmission?
refers to the spread of disease through droplets off moisture that contain pathogens
140
What is parenteral transmission?
transmission of pathogens through the breaks in the skin
141
What is blood-borne transmission?
pathogens carried in blood and body fluids of infected individuals can be transmitted
142
What is naturally acquired immunity? What is it also known as?
when a person has previously contracted disease and has recovered
143
What are the two forms of naturally acquired immunity?
Active immunity: when the host is involved
Passive immunity: antibodies from an outside source
144
What is artificially acquired immunity? Examples?
when the body has not been exposed to a disease, it has not developed antibodies and is completely defenseless
Immunization/Vaccination
145
What are the main routes from patient to dental team
Direct contact: patient's blood or saliva
Droplet infection: mucosal surfaces
Indirect contact: contaminated surfaces/instruments
146
How can droplet infection occur in a dental setting?
occurs when a dental team member inhales droplets from the handpiece or air-water syringe
147
What are some infection control measures to prevent disease transmission in patient to dental team?
wearing gloves
practicing handwashing
using masks
applying rubber dams
using patient mouth rinses
148
How can team-to-patient disease transmission occur in a dental setting?
While unlikely, it can occur if the member has lesions or cuts while inside the patient’s mouth
149
What is the primary way patient-to-patient transmission can occur?
occurs when contaminated instruments used on one patient are transferred to another patient
150
What infection control measures help prevent patient-to-patient transmission?
instrument sterilization
surface barriers
handwashing
gloves
sterile instruments
151
How does Dental-to-community infection occur?
contaminated impressions sent to labs
contaminated equipment sent for repairs
contaminated members
152
How does Community-to-dental-to-patient infection occur?
municipal water that colonize the inside of the dental unit waterlines
patient can swallow contaminated water
153
What should be used, liquid or bar soap?
liquid as bar may transmit transmission
154
What are the proper steps for hand hygiene when using gloves?
- Wash your hands before putting on gloves.
- Dry your hands thoroughly to prevent bacterial growth.
- Put on gloves, ensuring they are intact.
- After glove use, carefully remove them to avoid contamination.
- Immediately wash your hands again after removing gloves
155
How should you choose the type of PPE to wear? What materials?
the anticipated exposure to infectious materials
fluid-resistant material
156
What is a mask worn for?
worn over the nose and mouth to protect from inhaling infectious organisms spread by aerosol of dental tools
157
What type of mask should be worn when splash or spatter is likeyl?
a mask with 95% filtration efficiency for particle 3-5 micrometers
158
What are the two most common types of masks?
dome-shaped and flat
159
Why is protective eyewear worn?
to protect the eyes against damage from aerosolized pathogens and flying debris that could cause blindness
160
If you wear prescription glasses or lenses what must be added to protective eyewear?
protective side and bottom shields
161
If you leave the chairside for any reason what should be used in addition to gloves?
overgloves
162
What are the most common gloves used in patient care?
latex/vinyl examination/procedure gloves
163
What are overgloves also known as, and what are they made of?
food handler gloves
lightweight, cheap, clear plastic
164
When are sterile gloves worn?
hospital operating rooms: when invasive procedures, like cutting of bone or significant amounts of blood/saliva are present
165
When are utility gloves worn?
1. When the treatment room is cleaned and disinfected
2. While contaminated instruments are being cleaned
3. Surface cleaning and disinfection
166
How can you eliminate cross-contamination when using gloves?
anticipate tools needed during each procedure
use tongs/forceps to open cabinets or drawers
167
What are the 3 common types of allergies to latex?
Irritant Dermatitis = Surface
Type I and IV = Immune
168
What is irritant dermatitis, and what causes it?
a nonimmunologic skin reaction caused by contact with substances that produce chemical irritation
169
What factors contribute to irritant dermatitis?
Frequent hand washing
incomplete rinsing of soaps
cornstarch in gloves
excessive perspiration
failure to dry hands properly
170
What is the most common latex allergy
Type IV
171
What is Type IV latex allergy, what causes it?
a delayed contact reaction that involves the immune system, caused by the chemical used to process the latex
NOT PROTEINS
172
Why should latex gloves never be worn when handling chemicals
chemicals can pass through latex and cause irritation that may be mistakenly identified as allergic reaction
173
What is the most serious latex allergy that may cause death?
Type I
174
What causes Type I latex allergy?
A response to the proteins found in latex
175
What 3 groups should waste be separated into?
general waste
hazardous waste
Infectious waste
176
What is hazardous waste?
items that are a threat to humans and the environment
177
What is infectious waste?
items that are capable of transmitting an infectious disease
178
What are the three types of infectious waste?
blood and blood-soaked
pathologic
sharps
179
What CDC Guideline divided environmental surfaces into housekeeping and clinical contact surfaces?
CDC Guidelines for Infection Control in Dental Healthcare Settings - 2003
180
What are housekeeping surfaces?
floors, walls, and sinks
181
What are clinical contact surfaces?
areas directly contaminated during dental procedures or by the dental team's gloved hands
182
What should clinical contact surfaces be divided into?
1. touch
2. transfer
3. splash, spatter, and droplet
183
What are "touch" clinical contact surfaces?
directly touched and contaminated
handles, pens
barrier protected or cleaned between patients
184
What are "transfer" clinical contact surfaces?
not directly touched, but are touched by contaminated instruments
barrier protected or cleaned between patients
185
When should "splash, spatter, and droplet" clinical contact surfaces be cleaned?
daily
186
When and how should the HVE be cleaned?
What should NEVER be used?
at the end of the day
by flushing a detergent or water-base-detergent-disinfectant
NEVER USE BLEACH (sodium hypchlorite)
187
What are clinical instruments?
items that are used to penetrate soft tissue or bone
188
How should critical instruments be sterilized?
since they have the greatest risk of transmission, heat should be used to sterilize
189
What are semi-critical instruments?
instruments that touch the mucous membrane or non-intact skin
190
How should you sterilize semi-critical instruments?
using heat or high-level disinfection
191
What are noncritical instruments?
Only contact intact skin
192
How should noncritical instruments be cleaned?
using an EPA-registered intermediate-level or low level after each patient
193
Where should the instrument-processing/sterilization be located in the dental office?
centrally, to allow easy access from all patient care areas
194
What does the ideal instrument processing area look like?
1. dedicated to instrument processing
2. should be physically separated from the operatories and dental lab
3. should not be part of a common walkway
195
What are the 3 ways an instrument may be cleaned?
handscrubbing, ultrasonic cleaning, or instrument washing machines
196
What is a holding solution?
A liquid that instruments should be placed into if they cannot be cleaned immediately to prevent the drying of blood and debris
197
When should a holding solution be replaced?
at least twice daily and more frequently if it becomes clouded
198
What is the least desirable method of cleaning instruments?
hand scrubbing
199
What happens to carbon steel instruments in steam sterilization, how can we prevent this?
they will rust
preventable by using rust inhibitors or using dry heat
200
What is an unwrapped cycle also known as?
flash sterilization
201
What are the 3 common forms of heat sterilization?
steam sterilization
chemical vapor sterilization
dry heat sterilization
202
What temperature do dry heat sterilizers operate at?
320F - 375F
160C - 190C
203
What is Ethylene oxide sterilization?
a method of sterilization that is performed at low temperatures for 4-12 hours
204
What sterilant should be used for items that can't withstand heat sterilization? How long?
2% - 3.4% glutaraldehyde for 10 hours
205
Which organization is dentistry's resource for infection control and safety?
The Organization for Safety, Asepsis, and Prevention (OSAP)
206
Which organization regulates the manufacturing and labeling of medical devices?
Food and Drug Administration (FDA)
207
What is the regulatory agency associated with dentistry in ensuring the safety and effectiveness of disinfectants?
Environmental Protection Agency (EPA)
208
What federal regulatory agency is responsible for the safety and health of America's workers?
Occupational Safety and Health Administration (OSHA)
209
What is the primary federal agency for conducting and supporting medical research?
The National Institutes of Health (NIH)
210
What is the dental research institute of the NIH?
The National Institute of Dental and Craniofacial Research (NIDCR)
211
What is the federal institute responsible for conducting research and making recommendations for the prevention of work-related injury?
the National Institute for Occupational Safety and Health (NIOSH)
212
When is a chemical considered hazardous?
1. Can ignite
2. Can react or explode
3. Is corrosive
4. Is toxic
213
What is the Hazard Communication Standard (HCS), and when was it issued?
The HCS, also known as the Employee Right-to-Know Law, was issued by OSHA in 1983 to inform employees about workplace chemical hazards.
214
What are the three major areas of change in the HCS?
Hazard classification, labels, and safety data sheets (SDS).
215
When is staff training required?
1. When a new employee is hired
2. When a new chemical is introduced to the workplace
3. Once a year, for all continuing employees
216
How long should the records of training sessions be kept for?
5 years
217
What type of material are teeth considered?
potentially infectious
218
How do you dispose of extracted teeth that contain amalgam?
immersion in fresh, full-strength glutaraldehyde
219
What type of material is radiographic fixer considered? Why?
Hazardous, due to the high silver content
220
Germicidal solutions with greater than 2% glutaraldehyde are to be managed as what type of waste?
hazardous
