DHA Infection Control & Prevention 5 — Questions and Answers
Question 1: Which of the following pathogens requires airborne precautions (negative pressure room + N95 respirator)?
- Influenza A
- Meningococcal meningitis
- Pulmonary tuberculosis (Correct answer)
- MRSA wound infection
Correct answer: Pulmonary tuberculosis
Pulmonary tuberculosis is transmitted via small airborne droplet nuclei that remain suspended in air, requiring airborne precautions and N95 respirators.
Question 2: The Spaulding classification categorizes medical devices to determine the level of disinfection or sterilization needed. Which category applies to a laryngoscope blade?
- Critical — requires sterilization
- Semi-critical — requires high-level disinfection (Correct answer)
- Non-critical — requires low-level disinfection
- Non-critical — requires intermediate-level disinfection
Correct answer: Semi-critical — requires high-level disinfection
Laryngoscope blades contact mucous membranes but do not penetrate sterile tissue, classifying them as semi-critical and requiring at minimum high-level disinfection.
Question 3: A multidrug-resistant organism (MDRO) outbreak is suspected on a ward. Which initial action is MOST appropriate by the infection control team?
- Immediately close the ward to new admissions
- Conduct a point prevalence survey and review microbiology data (Correct answer)
- Transfer all colonized patients to ICU
- Increase antibiotic prophylaxis for all ward patients
Correct answer: Conduct a point prevalence survey and review microbiology data
Investigating an MDRO outbreak begins with a point prevalence survey and review of microbiology culture data to identify the scope and source.
Question 4: Which of the following correctly describes 'colonization' in infection control terminology?
- Presence of a pathogen causing active signs and symptoms
- Presence of a pathogen without causing clinical signs or symptoms (Correct answer)
- An immune response to a pathogen without infection
- A transient pathogen on intact skin that is removed by hand washing
Correct answer: Presence of a pathogen without causing clinical signs or symptoms
Colonization means a pathogen is present and multiplying on or in the host without causing clinical disease or an immune response.
Question 5: Healthcare-associated infections (HAIs) related to central venous catheters (CVCs) can be reduced by implementing a bundle approach. Which element is NOT part of the standard CVC insertion bundle?
- Hand hygiene before insertion
- Maximum sterile barrier precautions
- Chlorhexidine skin antisepsis
- Routine scheduled catheter changes every 72 hours (Correct answer)
Correct answer: Routine scheduled catheter changes every 72 hours
Evidence does not support routine scheduled CVC changes; catheters should be removed when no longer clinically necessary, not on a fixed schedule.
Question 6: In the chain of infection, which link is targeted when a patient with active pulmonary tuberculosis is placed in a negative pressure isolation room?
- Susceptible host
- Portal of entry
- Mode of transmission (Correct answer)
- Reservoir
Correct answer: Mode of transmission
Placing the patient in a negative pressure room interrupts the airborne mode of transmission by containing droplet nuclei and preventing their spread to others.
Question 7: According to standard precautions, when should a healthcare worker wear a mask and eye protection during patient care?
- Only when caring for patients with known respiratory infections
- Whenever there is a risk of splashing or spraying of blood, body fluids, or secretions (Correct answer)
- Only during aerosol-generating procedures
- Whenever entering a patient room regardless of activity
Correct answer: Whenever there is a risk of splashing or spraying of blood, body fluids, or secretions
Standard precautions require mask and eye protection whenever there is a reasonable anticipation of splashes or sprays of blood, body fluids, secretions, or excretions.
DHA Infection Control & Prevention 5
Which of the following pathogens requires airborne precautions (negative pressure room + N95 respirator)?