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CDC Infection Preventionist Post Test Questions with
Correct Answers and explanations LATEST THIS YEAR -
JUST RELEASED
Summarized Exam Coverage – CDC Infection Preventionist Post Test
The CDC Infection Preventionist training post-test covers: chain of infection (reservoir, portal of exit,
mode of transmission, portal of entry, susceptible host), standard and transmission-based precautions
(contact, droplet, airborne), hand hygiene (indications, technique, product selection), personal
protective equipment (donning/doffing order, selection), environmental infection control (cleaning,
disinfection, sterilization), safe injection practices (single-dose vials, needle handling), respiratory
hygiene/cough etiquette, surveillance and outbreak investigation (case definitions, line listings, attack
rates), construction and renovation risk assessment (ICRA), antimicrobial stewardship basics,
occupational health (exposures, post-exposure management), and healthcare – associated infection
(HAI) prevention strategies (CLABSI, CAUTI, SSI, VAE).
1. A resident in a long-term care facility develops a fever and cough three days after a visitor with
confirmed influenza spent an hour in the resident’s room. What is the most likely mode of transmission?
A) Airborne
B) Droplet
C) Vehicle (contaminated food)
D) Vector-borne
Answer: B — Influenza spreads primarily via large respiratory droplets generated by coughing, sneezing,
or talking within 3–6 feet of a susceptible person.
2. During an outbreak of norovirus on a skilled nursing unit, you observe a staff member entering a
resident’s room wearing gloves but no gown. The resident has active vomiting and diarrhea. Which
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element of transmission-based precautions is missing?
A) Eye protection
B) Contact precautions (gown) due to environmental contamination
C) N95 respirator
D) Shoe covers
Answer: B — Norovirus requires contact precautions including gown and gloves because the virus is
highly contagious via contaminated surfaces and body fluids.
3. A healthcare worker sustains a needlestick injury while injecting a patient with unknown bloodborne
infection status. What is the first action the worker should take?
A) Report to employee health within 72 hours
B) Wash the wound with soap and water immediately
C) Squeeze the wound to encourage bleeding
D) Apply a bandage and finish the shift
Answer: B — Immediate washing with soap and water reduces infection risk; squeezing is not
recommended and may cause tissue damage.
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4. A central line–associated bloodstream infection (CLABSI) rate increases on a surgical unit over three
consecutive months. Which surveillance step should the infection preventionist take first?
A) Immediately remove all central lines
B) Review central line insertion and maintenance practices and conduct a root cause analysis
C) Increase chlorhexidine bathing to twice daily
D) Change all central line dressings every 24 hours
Answer: B — Investigating practices (hand hygiene, maximal sterile barriers, chlorhexidine skin prep, hub
disinfection) is the first step to identify and correct gaps.
5. In the operating room, a surgical instrument falls onto the floor before a procedure. The instrument
was sterile in its package, but the package is intact and dry. What should the scrub nurse do?
A) Use the instrument because the package is intact
B) Consider it contaminated because the outer package touched the floor; do not use it
C) Wipe the package with alcohol and open it
D) Use the instrument after rinsing it with sterile water
Answer: B — Once the sterile package touches an unsterile surface (floor), the sterility is compromised; a
new sterile instrument must be used.
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6. A resident in a long-term care facility is placed on Contact Precautions for
methicillin-resistant Staphylococcus aureus (MRSA) in a wound. Which of the following is required for a
staff member entering the room to change the wound dressing?
A) Surgical mask
B) N95 respirator
C) Gown and gloves
D) Eye protection only
Answer: C — Contact Precautions require gown and gloves for any entry into the room when contact
with the resident or environment is anticipated.
7. During an outbreak of Aspergillus in a bone marrow transplant unit, environmental sampling links the
fungus to construction dust from a renovation two floors below. What infection control measure should
have been implemented before construction began?
A) High-efficiency particulate air (HEPA) filtration of the unit
B) An infection control risk assessment (ICRA) with containment barriers and negative pressure in
construction zones
C) Daily mopping of the unit
CDC Infection Preventionist Post Test Questions with
Correct Answers and explanations LATEST THIS YEAR -
JUST RELEASED
Summarized Exam Coverage – CDC Infection Preventionist Post Test
The CDC Infection Preventionist training post-test covers: chain of infection (reservoir, portal of exit,
mode of transmission, portal of entry, susceptible host), standard and transmission-based precautions
(contact, droplet, airborne), hand hygiene (indications, technique, product selection), personal
protective equipment (donning/doffing order, selection), environmental infection control (cleaning,
disinfection, sterilization), safe injection practices (single-dose vials, needle handling), respiratory
hygiene/cough etiquette, surveillance and outbreak investigation (case definitions, line listings, attack
rates), construction and renovation risk assessment (ICRA), antimicrobial stewardship basics,
occupational health (exposures, post-exposure management), and healthcare – associated infection
(HAI) prevention strategies (CLABSI, CAUTI, SSI, VAE).
1. A resident in a long-term care facility develops a fever and cough three days after a visitor with
confirmed influenza spent an hour in the resident’s room. What is the most likely mode of transmission?
A) Airborne
B) Droplet
C) Vehicle (contaminated food)
D) Vector-borne
Answer: B — Influenza spreads primarily via large respiratory droplets generated by coughing, sneezing,
or talking within 3–6 feet of a susceptible person.
2. During an outbreak of norovirus on a skilled nursing unit, you observe a staff member entering a
resident’s room wearing gloves but no gown. The resident has active vomiting and diarrhea. Which
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element of transmission-based precautions is missing?
A) Eye protection
B) Contact precautions (gown) due to environmental contamination
C) N95 respirator
D) Shoe covers
Answer: B — Norovirus requires contact precautions including gown and gloves because the virus is
highly contagious via contaminated surfaces and body fluids.
3. A healthcare worker sustains a needlestick injury while injecting a patient with unknown bloodborne
infection status. What is the first action the worker should take?
A) Report to employee health within 72 hours
B) Wash the wound with soap and water immediately
C) Squeeze the wound to encourage bleeding
D) Apply a bandage and finish the shift
Answer: B — Immediate washing with soap and water reduces infection risk; squeezing is not
recommended and may cause tissue damage.
, Page 3 of 132
4. A central line–associated bloodstream infection (CLABSI) rate increases on a surgical unit over three
consecutive months. Which surveillance step should the infection preventionist take first?
A) Immediately remove all central lines
B) Review central line insertion and maintenance practices and conduct a root cause analysis
C) Increase chlorhexidine bathing to twice daily
D) Change all central line dressings every 24 hours
Answer: B — Investigating practices (hand hygiene, maximal sterile barriers, chlorhexidine skin prep, hub
disinfection) is the first step to identify and correct gaps.
5. In the operating room, a surgical instrument falls onto the floor before a procedure. The instrument
was sterile in its package, but the package is intact and dry. What should the scrub nurse do?
A) Use the instrument because the package is intact
B) Consider it contaminated because the outer package touched the floor; do not use it
C) Wipe the package with alcohol and open it
D) Use the instrument after rinsing it with sterile water
Answer: B — Once the sterile package touches an unsterile surface (floor), the sterility is compromised; a
new sterile instrument must be used.
, Page 4 of 132
6. A resident in a long-term care facility is placed on Contact Precautions for
methicillin-resistant Staphylococcus aureus (MRSA) in a wound. Which of the following is required for a
staff member entering the room to change the wound dressing?
A) Surgical mask
B) N95 respirator
C) Gown and gloves
D) Eye protection only
Answer: C — Contact Precautions require gown and gloves for any entry into the room when contact
with the resident or environment is anticipated.
7. During an outbreak of Aspergillus in a bone marrow transplant unit, environmental sampling links the
fungus to construction dust from a renovation two floors below. What infection control measure should
have been implemented before construction began?
A) High-efficiency particulate air (HEPA) filtration of the unit
B) An infection control risk assessment (ICRA) with containment barriers and negative pressure in
construction zones
C) Daily mopping of the unit
