1At the start of the 20th century, major US causes of death included pneumonia, TB, gastroenteritis, and ______.
diphtheria
2What two situations (groups of people) find microbial infections especially dangerous today?
Being immunocompromised; living in an underdeveloped country
3Microbes are essential to life because they recycle ______ and inorganic material.
organic
4Which scientist first observed microbes, which he called "wee animalcules"?
Anton van Leeuwenhoek
5A disease-producing microorganism is called a ______.
pathogen
6An infection is called a disease only when it causes ______ to the host.
injury (tissue damage)
7What three abilities make pathogens harmful?
Multiply in large numbers and cause an obstruction
Cause tissue damage
Secrete exotoxins
8Organic substances secreted by pathogens that can cause high fever, nausea, vomiting, and shock are called ______.
exotoxins
9What are the four basic classifications of infectious agents?
Bacteria, viruses, fungi, and protozoan parasites
10Bacteria are single-celled organisms that lack a true ______.
nucleus
11Bacteria are prokaryotes, meaning they lack a nucleus and ______ organelles.
membrane-bound
12Cocci are ______-shaped bacteria.
round
13Bacilli are ______-shaped bacteria.
rod
14Spirilla are ______-shaped bacteria.
spiral
15Bacteria are routinely classified by shape using a simple staining technique called ______.
Gram staining
16Bacteria that form spores have a high ______ ability.
survival
17A bacterium makes a dormant, highly resistant internal structure called an ______ when nutrients are scarce.
endospore
18Which two medically important bacterial genera form endospores?
Bacillus and Clostridium
19Strep throat, Klebsiella pneumonia, and Clostridium botulinum food poisoning are caused by which infectious agent?
Bacteria
20Bacterial infections are controlled with antibiotics and ______.
sterilization
21Most bacteria are harmless or helpful and make up the body’s normal ______.
flora
22Why must radiology equipment and contrast materials be kept sterile?
To prevent bacterial spread between patients
23What are the smallest known disease-causing microorganisms?
Viruses
24Viruses need a ______ cell to live and reproduce.
host
25A viral particle that attaches to a host cell is called a ______.
virion
26A virus carries DNA or RNA (never both) inside a protein coat called a ______.
capsid
27The common cold, influenza, COVID-19, and RSV are all caused by which infectious agent?
Viruses
28A cold sore from herpes simplex is an example of a ______ viral infection that reappears sporadically.
latent
29Fungi are complex organisms that include yeasts and ______.
molds
30Fungi differ from bacteria in having a true ______.
nucleus (they are eukaryotes)
31Fungi commonly come from air, soil, water, and ______.
plants
32Thrush is an overgrowth of ______ in the mouth or throat.
Candida
33Ringworm, thrush, and athlete’s foot are infections caused by which infectious agent?
Fungi
34Fungi thrive in ______ and ______ environments.
warm; moist
35Fungi are spread by airborne ______ or direct contact.
spores
36Fungi that can grow as either a single-celled yeast or filamentous mold are called ______.
dimorphic
37The tiny, lightweight spores formed by molds are called ______.
conidia
38What are the four classifications of fungal infection?
Superficial
Cutaneous
Subcutaneous
Systemic
39Athlete’s foot is also known as tinea pedis?
True
40Protozoan parasites are single-celled organisms that live in or on a host and need ______ environments.
moist
41How are protozoan parasites spread?
Through an insect bite (e.g., mosquito) or by ingesting contaminated food or water
42Malaria and giardiasis are illnesses caused by which infectious agent?
Protozoan parasites
43Giardiasis is an intestinal infection caused by a microscopic ______.
parasite
44Malaria is caused by the protozoan ______ vivax.
Plasmodium
45How are protozoa grouped by motility?
Ameboid (slow flowing)
Flagellates (flagellum)
Ciliates (cilia)
Sporozoans (nonmotile)
46Some protozoa form a protective stage called a ______ that lets them survive outside a host.
cyst
47What are the six steps in the establishment of infectious disease?
Encounter, entry, spread, multiplication, damage, outcome
48For infection to develop, the host must be ______.
susceptible
49Infection occurs when the pathogen overcomes host ______.
defenses
50The first step, when a host comes into contact with a pathogen, is the ______.
encounter
51The strength of a microorganism is called its ______.
virulence
52What three factors determine whether an encounter leads to disease?
Virulence (strength) of the microbe
Dose (number of organisms)
Host defenses and immune status
53When microbes grow on or in a host without causing illness, it is called ______.
colonization
54Infections such as rubella and syphilis that cross the placenta to the unborn child are called ______ infections.
congenital
55What are four common portals of entry?
Digestive tract
Respiratory tract
Breaks in the skin
Urinary and genitourinary tracts
56Inhaling contaminated aerosols or dust gives pathogens entry through the ______ tract.
respiratory
57Cuts, wounds, needles, and vector bites let pathogens in through ______ in the skin.
breaks

58Mucous membranes and ______ trap particles and move them out of the body.
cilia
59Stomach and vaginal ______ help prevent pathogen entry.
acidity
60Tears and urine contain lysozyme, an enzyme that destroys ______.
bacterial cell walls
61What is the difference between ingression and penetration?
Ingression: microbes adhere to the cell surface and secrete toxins without deep invasion (e.g., diarrhea, pneumonia)
Penetration: microbes invade past the epithelial barrier (flagella, vectors, wounds)
62Direct spread of microorganisms in the body occurs through tissues and fluids such as the bloodstream and ______ system.
lymphatic

63Indirect spread occurs through contaminated instruments, hands, or ______.
surfaces
64An infection that stays at the site of entry is a ______ infection.
local

65What is the difference between a local and a systemic infection?
A local infection stays at the site of entry (e.g., an infected wound), whereas a systemic infection spreads through blood and lymph to the whole body.

66The time from overcoming host defenses until a substantial microbe population is reached is the ______ period.
incubation
67Direct damage occurs when microbes ______ and kill host cells.
multiply

68Indirect damage is caused by toxins or the body's own ______ response.
immune

69Fever, inflammation, and pain result from ______ injury.
tissue
70What are the three possible outcomes of an infection?
Host controls the infection and recovers
Infection causes disease or death
Pathogen remains in the body in a latent (inactive) state
71A pathogen that remains in the body in an inactive state is called ______.
latent
72What are the links in the chain of infection?
Textbook: host, infectious microorganism, mode of transmission, reservoir (four factors)
PPT: infectious agent, reservoir, portal of exit, mode of transmission, portal of entry, susceptible host (six links)
73If the chain of infection is broken at any link, the infection ______.
cannot continue (it ceases)
74Who introduced the germ theory of disease in 1876?
Robert Koch
75What factors increase the host's risk of infection?
Age (very young or very old)
Poor nutrition
Chronic illness
Stress
Fatigue
Immunosuppression

76What are the five main routes of transmission?
Contact, droplet, airborne, vehicle, and vector

77A contaminated object or surface where a pathogen may live is called a ______.
fomite

78Transmission by contaminated food, water, or a medical device is ______ transmission.
vehicle
79Malaria is carried by a vector, the ______.
mosquito
80The deer tick is a vector for ______ disease.
Lyme
81What is the difference between a vehicle and a vector?
A vehicle is a nonliving carrier such as food, water, or a medical device, whereas a vector is a living animal or insect such as a mosquito, flea, or tick.

82Airborne particles may be blocked with an ______ mask.
N95
83Hand hygiene and ______ are key to breaking transmission.
PPE
84What is the difference between exogenous and endogenous transmission?
Exogenous: from a microbe in the environment (contact, vector, fomite)
Endogenous: from the body's own normal flora moving to a new site
85Any place where pathogens can survive and multiply is called a ______.
reservoir
86What are three common types of reservoirs?
Humans (patients or healthcare workers)
Animals
Environment (water, soil, contaminated equipment)
87Infections passed from animals to humans, such as rabies, are called ______ infections.
zoonotic
88An infected person with no symptoms who can still spread disease is called a ______.
carrier
89Proper cleaning and disinfection eliminate ______ of infection.
reservoirs
90Infections that develop while receiving medical care are called ______ infections.
healthcare-associated (HAIs)
91Nosocomial infections typically show signs about ______ hours after contact.
Textbook: about 72 hours
PPT: 48 hours
92What are four common types of HAI?
Urinary tract infection from a contaminated catheter
Infection from improper aseptic handwashing
Airborne respiratory infection
Bloodstream infection from pathogens at an instrument or injection site
93Two common HAI-causing organisms are MRSA and ______.
C. diff
94What are three common sources of HAIs?
Contaminated instruments or surfaces
Invasive devices (catheters, IV lines)
Poor hand hygiene or breaks in aseptic technique
95An infection resulting from a physician's intervention is called ______.
iatrogenic
96What is the most common nosocomial infection, and what causes it?
Urinary tract infection, introduced by a Foley (urinary) catheter
97Patients with weakened immune systems are called ______ patients.
compromised
98What causes compromised immunity?
Age (very young or elderly)
Disease (cancer, HIV/AIDS, diabetes)
Medical treatments (chemotherapy, radiation, steroids, transplants)
Imbalanced gut flora
99Reverse isolation requires foot covers, IR covers, and ______.
PPE
100Healthcare workers can be ______ carriers who spread infection without symptoms.
asymptomatic

101Healthcare worker transmission often occurs through hands, clothing, or ______.
equipment
102Normal flora is found on the skin, mouth, nose, throat, and ______ tract.
digestive

103When can normal flora cause infection?
When it enters sterile areas (urinary tract, lungs, spinal fluid, nervous system) or when the immune system is weak

104Which common healthcare items can harbor pathogens?
Bed rails, tables, keyboards, imaging equipment, linens, gowns, and reusable supplies such as blood pressure cuffs

105If cleaning is inadequate, infections spread through ______ contact.
indirect
106Blood-borne pathogens are microorganisms found in human blood and ______.
body fluids
107Which blood-borne virus is the most common and most infectious?
Hepatitis B virus (HBV)
108Hepatitis B can be prevented with a highly effective ______.
vaccine
109Which blood-borne virus has no vaccine?
Hepatitis C virus (HCV)
110Hepatitis B can cause liver dysfunction, cirrhosis, and the need for a liver ______.
transplant
111Untreated HIV may lead to ______.
AIDS (acquired immunodeficiency syndrome)
112HIV specifically infects the immune system's ______ T cells.
CD4+
113How can blood-borne pathogens enter the body?
Needlestick injuries, cuts, or mucous membranes
114Invasive procedures break the body's natural ______.
barriers
115Invasive procedures create a ______ of entry for microorganisms.
portal
116What are the three types of constitutive (innate) defenses?
Mechanical, chemical, and cellular
117Skin, mucous membranes, and cilia are ______ barriers.
mechanical
118Stomach acid, tears, and saliva are ______ barriers.
chemical
119Which cells attack cells that look abnormal or infected?
Natural killer (NK) cells
120Phagocytes engulf and destroy foreign particles through a process called ______.
phagocytosis
121Fever and inflammation help ______ microbial growth.
slow
122Normal flora protects the body by ______ with harmful microbes.
competing
123Normal flora is disrupted by antibiotics, illness, or poor ______.
hygiene
124The goal of chemotherapy is ______ toxicity: harming the pathogen but not the patient's cells.
selective

125Which drug types treat bacteria, viruses, fungi, and protozoa?
Antibiotics, antivirals, antifungals, and antiparasitics

126The most difficult infections to treat are MRSA, C. diff, and sometimes ______.
TB
127Overuse or misuse of antimicrobial drugs can lead to drug-______ strains.
resistant
128What is the difference between -static and -cidal drugs?
-static drugs inhibit growth but do not kill (e.g., tetracyclines), whereas -cidal drugs kill microbes (e.g., penicillins).
129Vaccines introduce a weakened form of a disease so the body makes antibodies and ______ cells.
memory
130Immunity gained when the body makes its own antibodies is ______ immunity.
active
131Immunity passed from a mother to her child in utero is ______ immunity.
passive
132______ immunity occurs when enough of a community is immune that person-to-person spread is unlikely.
Herd (population)
133A booster addresses waning immunity or evolving strains; the annual ______ shot is one example.
flu
134The MMR vaccine protects against measles, mumps, and ______.
rubella (German measles)
135What three environmental factors are controlled in healthcare facilities?
Proper ventilation
Humidity and temperature
Surface cleanliness
136Microorganisms grow best in warm and ______ places.
humid
137Most human pathogens grow best at body temperature, ______.
37°C (98.6°F)
138What are the three cleaning categories?
Cleaning (physically removing dirt)
Disinfection (chemicals kill most pathogens but not spores)
Sterilization (destroys all microorganisms and spores)
139Disinfection kills most pathogens but not ______.
spores
140Sterilization is the complete destruction of all microorganisms and ______.
spores
141Asepsis means free from ______ microorganisms.
infection-causing
142What is the difference between medical and surgical asepsis?
Medical asepsis (clean technique) reduces the number of microorganisms, whereas surgical asepsis (sterile technique) eliminates all microorganisms and spores.
143Cleaning a stethoscope with alcohol between patients is an example of ______ asepsis.
medical
144Sterile items must be kept ______ waist level at all times.
above
145Surgical asepsis may be used for biopsies, mammographic procedures, and OR cases with a ______.
C-arm
146Chlorine and bleach are effective against bacteria and ______.
viruses

147Alcohol is ineffective against spores because it ______ quickly.
evaporates

148Iodine is used for skin asepsis but has a high rate of skin ______.
irritation

149Which disinfectant breaks down into water and oxygen and is more environmentally safe?
Hydrogen peroxide

150Most chemical methods cannot kill spores; stubborn examples are C. diff and ______.
TB
151A disinfectant applied topically to living tissue is called an ______.
antiseptic
152Which gas sterilizes electronic and plastic equipment damaged by heat?
Ethylene oxide
153The most common physical method of sterilization is steam under pressure, called ______.
autoclaving
154How many minutes does autoclaving take at 121°C (250°F)?
Textbook: 15 minutes (at 15 lb/in2)
PPT: 20 consecutive minutes
155Dry heat is used for items ruined by moisture, such as oils, glass, and ______.
powders
156How hot and how long does dry heat sterilization run?
Textbook: 160°C (320°F) for 120 minutes
PPT: very high temperature (no values given)
157Using moderate heat on heat-sensitive materials is called ______.
pasteurization
158UV radiation uses short-wavelength ______ light to inactivate microorganisms.
ultraviolet
159Air filtration removes microorganisms from air in ______ systems.
ventilation
160Rank the physical methods by commonality.
1. Steam under pressure (autoclaving)
2. Dry heat
3. Pasteurization
4. UV radiation
5. Air filtration
161What is the single most effective method to prevent infection transmission?
Handwashing (hand hygiene)
162Who showed in 1846 that handwashing prevents the spread of infection?
Dr. Semmelweis
163Wash hands before and after every ______ contact.
patient
164How long should handwashing last?
Textbook: up to 7-8 minutes may be needed to remove transients from soiled hands
PPT: at least 20 seconds with soap and warm water
165Alcohol-based sanitizer is acceptable only when hands are not visibly ______.
soiled
166During medically aseptic handwashing, keep the hands lower than the ______.
elbows
167During handwashing, treat the sink as ______.
contaminated
168Standard precautions are used for ______ patient regardless of diagnosis.
every
169Always assume every patient is ______.
infectious
170What are the elements of standard precautions?
Hand hygiene
PPE
Respiratory hygiene and cough etiquette
Safe injection practices
Environmental cleaning
Linen and waste management
171Blood and body fluid waste goes in the ______ bin.
biohazard
172Wear ______ gloves for every patient.
new
173Never ______ or wash disposable gloves.
reuse
174What are the common types of PPE?
Gloves, gowns, masks and respirators, goggles or face shields

175Choose PPE based on the level of ______ risk.
exposure
176Goggles or face shields protect the eyes from ______.
splashes
177Never ______ used needles.
recap

178Needles and sharps are disposed of in ______ containers.
puncture-resistant

179If recapping is unavoidable, which technique can be used?
The one-handed scoop technique (or a recapping device)
180What must you do after any sharps injury?
Report it and follow up immediately
181What PPE is worn before handling a biohazard spill?
Gloves, gown, and eye protection
182What can be used to clean a biohazard spill area?
A hospital-approved disinfectant (e.g., bleach solution)
183Transmission-based precautions are used in addition to ______ precautions.
standard
184What are the three categories of transmission-based precautions?
Airborne, droplet, and contact
185Airborne precautions protect against tiny particles that remain ______ in the air.
suspended
186Airborne precautions require a ______-pressure isolation room.
negative
187In a negative-pressure room, air rushes ______ the room when the door opens.
into
188For airborne precautions, healthcare workers wear an ______ respirator or higher.
N95
189Name diseases that require airborne precautions.
TB, measles (rubeola), chickenpox (varicella), and shingles
190Shingles is a variation of the ______ virus that reactivates in older adults.
varicella
191Droplet precautions protect against large respiratory droplets that travel up to ______ feet.
3
192Droplet precautions apply to particles ______ microns or larger.
5
193Name diseases that require droplet precautions.
Textbook: rubella, mumps, influenza, adenovirus
PPT: influenza, meningitis, mumps, pneumonia
194Droplet precautions require a ______ mask and sometimes eye protection.
surgical
195During transport, a patient on airborne or droplet precautions wears a ______.
surgical mask
196Name diseases that require contact precautions.
Textbook: MRSA, hepatitis A, impetigo, varicella (zoster)
PPT: MRSA, C. diff, norovirus, impetigo
197Sterilization removes ______, which make C. diff hard to kill.
spores
198Contact precautions require ______ and ______ for all patient or surface contact.
gloves; gown
199Contact precautions use ______ equipment when possible.
dedicated
200Contact precautions technique follows a ______-step protocol.
21
201In what order is PPE removed when leaving a contact precautions room?
Textbook: gown first, then gloves, then cap and mask, then wash hands
PPT: gloves first, then gown into biohazard trash, then wash hands
202Spores often survive handwashing, heat, and ______.
chemicals
203Each cassette in a contact precautions exam is placed in a protective ______.
bag
204When removing the mask, touch only the strings or ______.
elastic
205Label the five routes of disease transmission (left to right).

1. Direct contact
2. Indirect contact
3. Droplet
4. Airborne
5. Vector/vehicle

206Which route of transmission is shown by the icon above the "?" box (icon 1 of 5, left to right)?

Direct contact

207Which route of transmission is shown by the icon above the "?" box (icon 2 of 5, left to right)?

Indirect contact

208Which route of transmission is shown by the icon above the "?" box (icon 3 of 5, left to right)?

Droplet

209Which route of transmission is shown by the icon above the "?" box (icon 4 of 5, left to right)?

Airborne

210Which route of transmission is shown by the icon above the "?" box (icon 5 of 5, left to right)?

Vector/vehicle
