CIC Outbreak Investigation 3

Question 1

In a hospital outbreak of Serratia marcescens in a neonatal ICU, which source is most commonly implicated?

Accepted Answer

Shared multi-dose medication vials or contaminated IV fluids

Answer

Serratia marcescens outbreaks in NICUs are frequently linked to contaminated multi-dose medication vials, IV fluids, or infusion equipment.

Question 2

Which statistical test is most appropriate to determine if the difference in attack rates between exposed and unexposed groups is statistically significant?

Accepted Answer

Chi-square test or Fisher's exact test

Answer

Chi-square test (or Fisher's exact test for small cell counts) is used to compare proportions such as attack rates between two groups in outbreak investigations.

Question 3

An ICP notes that a unit has had 5 MRSA infections in the past month compared to a baseline of 1 per month. What is the FIRST action?

Accepted Answer

Confirm case definitions and review whether cases meet healthcare-associated criteria

Answer

Before declaring an outbreak, the ICP must first confirm case definitions and verify that cases are true healthcare-associated infections to avoid pseudo-outbreaks.

Question 4

Which molecular typing method is considered the gold standard for clonal relatedness in outbreak investigations of Staphylococcus aureus?

Accepted Answer

Whole genome sequencing (WGS)

Answer

Whole genome sequencing is now considered the most discriminatory method for determining clonal relatedness and is increasingly used as the gold standard in outbreak investigations.

Question 5

During a COVID-19 outbreak investigation in a hospital, what is the primary purpose of contact tracing?

Accepted Answer

To identify exposed individuals and implement quarantine or monitoring

Answer

Contact tracing identifies individuals exposed to confirmed cases so they can be quarantined, monitored for symptoms, and tested to break chains of transmission.

CIC - Certification in Infection Prevention and Control Practice Test

CIC - Certification in Infection Prevention and Control Practice Test

CIC Outbreak Investigation 3