CIC Outbreak Investigation 2

Question 1

Which measure is used to quantify the association between an exposure and illness in a cohort study during an outbreak investigation?

Accepted Answer

Relative risk

Answer

Relative risk (risk ratio) is the measure of association used in cohort studies, comparing the risk of illness among exposed versus unexposed individuals.

Question 2

During an outbreak of Clostridioides difficile in a long-term care facility, which environmental surface is most commonly implicated as a reservoir?

Accepted Answer

Toilet seats, commodes, and bathroom surfaces

Answer

C. difficile spores persist on environmental surfaces especially in bathrooms and can survive for months, making toilets and commodes common reservoirs.

Question 3

An epidemic curve showing a prolonged plateau with cases continuing over several weeks most likely indicates which type of outbreak?

Accepted Answer

Continuous common-source outbreak

Answer

A continuous common-source outbreak produces a prolonged plateau on the epidemic curve because ongoing exposure to the contaminated source continues over time.

Question 4

When calculating an attack rate stratified by exposure status, what is the primary purpose of stratification?

Accepted Answer

To identify confounding variables and effect modifiers

Answer

Stratification helps identify confounders and effect modifiers by examining whether the exposure-disease association differs across subgroups.

Question 5

A foodborne outbreak affects guests at a wedding reception. Which investigative approach would best identify the implicated food item?

Accepted Answer

Cohort study with food-specific attack rates among attendees

Answer

A cohort study calculating food-specific attack rates among all attendees is the most efficient method when the exposed population is well-defined and enumerable.

CIC - Certification in Infection Prevention and Control Practice Test

CIC - Certification in Infection Prevention and Control Practice Test

CIC Outbreak Investigation 2