Practice Exam Part 2

35. 35. The infection preventionist is reviewing a construction project’s proposed mitigation strategies to minimize airborne contamination. What should the air pressure in the adjacent patient care unit be in comparison to the construction site?

• Neutral

• Increased

• Decreased

• Laminar

Answer explanation

Rationale: Construction sites should have negative pressure compared with adjacent patient-care areas to prevent airborne contamination from construction being transmitted into the patient spaces. CBIC

Core Competency: Environment of Care

36. 36. Which of the following is a measure of central tendency?

• Prevalence rate

• Incidence rate

• Confidence interval

• Median

Answer explanation

Rationale: A measure of central tendency is a single value that attempts to describe a set of data by identifying the central position within that set of data. The three types of data used as measures of central tendency are the mean, the median, and the mode. The mean is the average value for the data set. The median is the middle score for a set of data that has been arranged in order of magnitude. The mode is the most frequent score.

CBIC Core Competency: Surveillance and Epidemiologic Investigation

37. 37. Which type of immune cells are responsible for directly attacking and destroying infected or abnormal cells in the body?

• B cells

• Cytotoxic T cells

• Natural killer (NK) cells

• Macrophages

Answer explanation

Rationale: Cytotoxic T cells, also known as CD8+ T cells, play a crucial role in the cell-mediated immune response. These cells recognize and directly target infected or abnormal cells, inducing apoptosis (programmed cell death) to eliminate the threat. While other immune cells such as B cells produce antibodies, and macrophages engulf pathogens, cytotoxic T cells are specifically designed for cell-to-cell combat, making them essential for eliminating intracellular infections and cancerous cells.

CBIC Core Competency: Identification of Infectious Disease Processes

38. 38. In order to have a well-established program, infection prevention departments must be able to influence practice. This involves utilizing epidemiological principles to improve patient safety and reduce adverse events. Infection preventionists who integrate evidence-based practices into their routine work are employing what approach?

• Risk management strategies

• Clinical governance principles

• Implementation science methodologies

• Population health interventions

Answer explanation

Rationale: Implementation science is crucial for infection preventionists as it focuses on systematically integrating evidence-based practices into routine work processes. This approach provides frameworks and tools to overcome barriers to practice change, ensuring the effective translation of research evidence into practical application. By engaging in continuous improvement and sustainability efforts, implementation science helps infection preventionists refine interventions over time and maintain improvements in patient safety. Ultimately, by utilizing implementation science methodologies, infection preventionists can optimize their efforts to reduce adverse events and enhance patient outcomes in healthcare settings.

CBIC Core Competency: Management and Communication

39. 39. If chance is a likely explanation for the difference between a sample statistic and the corresponding null hypothesis population value, then what can be inferred?

• The difference is not statistically significant.

• The sample results are not compatible with the null hypothesis.

• The difference is statistically significant.

• The null hypothesis can be rejected.

Answer explanation

Rationale: A common use of statistics is hypothesis testing. A hypothesis is a statement of expected results. Hypothesis testing uses the distribution of a known area in the normal curve and estimates the likelihood (probability) that a result did not occur by chance. Significance levels show how likely a result is due to chance. In statistics, if a result is significant, it means that it is not due to chance. If chance is a likely explanation for the difference between a sample statistic and the corresponding null hypothesis population value, then the difference is not statistically significant.

CBIC Core Competency: Surveillance and Epidemiologic Investigation

40. 40. Following a cluster of Clostridioides difficile infections identified in the intensive care unit, an investigation revealed gaps in hand hygiene and glove use. To halt this outbreak, which link in the chain of infection must be addressed?

• a. Reservoir

• b. Host

• c. Mode of transmission

• d. Infectious agent

Answer explanation

Rationale: Addressing the mode of transmission is crucial to stopping the outbreak because Clostridioides difficile is primarily transmitted through the fecal-oral route. Hand hygiene and correct glove use interrupt this mode of transmission, preventing the spread of the pathogen within the healthcare setting. Figure PE1-1 illustrates the chain of infection.

CBIC Core Competency: Identification of Infectious Disease Processes

41. 41. The transport personnel find a patient’s wheelchair soiled with blood and calls the infection preventionist (IP) for cleaning recommendations. Which of the following methods should the IP recommend?

• Using a high-level disinfectant

• Application of an intermediate-level disinfectant

• Exposing the wheelchair to ultraviolet (UV) light disinfection

• Utilization of an advanced spectrum disinfectant

Answer explanation

Rationale: Surfaces contaminated with blood and body fluid should be disinfected between patients with an intermediate-disinfectant (i.e., EPAregistered hospital disinfectant with tuberculocidal claim.) Intermediate-level disinfection refers to the use of an agent that kills a wider range of pathogens than a low level disinfectant but does not kill bacterial spores. Intermediate-level disinfection should be considered for environmental surfaces that are visibly contaminated with blood. However, a low-level disinfectant with a label claim against HBV and HIV could also be used.

CBIC Core Competency: Cleaning, Disinfection, Sterilization of Medical Devices

and Equipment

42. 42. A healthcare worker (HCW) seeks guidance from employee health after an unprotected direct exposure to a patient with confirmed monkeypox. What guidance should be provided to the exposed HCW?

• The HCW should be removed from duty pending medical evaluation and risk assessment with a physician.

• Asymptomatic HCW’s must be excluded from providing patient care for five days after exposure.

• Asymptomatic HCWs may continue working but should perform daily self-monitoring for signs and symptoms and undergo active surveillance for 21 days after the last exposure.

• The HCW may continue working but must adhere to strict infection control measures, including wearing appropriate personal protective equipment, to minimize the risk of transmission.

Answer explanation

Rationale: Asymptomatic healthcare workers (HCWs) with exposures to mpox virus do not need to be excluded from work, but should be monitored (e.g., at least a daily assessment conducted by the exposed HCW for signs and symptoms of mpox infection) for 21 days after their last exposure.

CBIC Core Competency: Employee/Occupational Health

43. 43. An acute care facility experiences an outbreak of Serratia marcescens bloodstream infections. After the outbreak is under control and no new cases are being reported, the IP wants to find the source of the outbreak. What is the most appropriate epidemiology study design to identify the outbreak’s source?

• Retrospective cohort study

• Prospective cohort study

• Case-control study

• Cross-sectional study

Answer explanation

Rationale: Case-control studies group people by disease status and then investigate past exposures with the objective of identifying exposures that are more common to cases than to controls. This is an appropriate study design for this example because there are existing cases, and the infection preventionist is trying to identify the exposures that are associated with the bloodstream infections.

CBIC Core Competency: Surveillance and Epidemiologic Investigation

44. 44. The flooring in the operating room (OR) needs to be completely replaced. What class of precautions is required for this level of construction in the infection control risk assessment (ICRA) related to this renovation project in the OR?

• Class I

• Class II

• Class IV

• Class V

Answer explanation

Rationale: In the context of infection control risk assessment (ICRA) for construction projects, Class V precautions are recommended for areas with the highest risk of infection transmission, such as operating rooms (ORs). Class V precautions involve extensive measures to minimize the risk of airborne contamination and infection spread during construction or renovation activities in critical healthcare environments. It includes complete critical barriers meeting NFPA 241 requirements. Barriers must extend to the ceiling. Construct anteroom large enough for equipment staging, cart cleaning, workers. The anteroom must be constructed adjacent to entrance of construction work area. Negative airflow pattern must be maintained from the entry point to the anteroom and into the construction area. The airflow must cascade from outside to inside the construction area. The entire construction area must remain negatively pressurized.

CBIC Core Competency: Environment of Care