CBIC Surveillance 4 — Questions and Answers
Question 1: Which of the following best describes 'syndromic surveillance'?
- Surveillance based on confirmed laboratory diagnoses
- Monitoring of pre-diagnostic clinical indicators to detect outbreaks early (Correct answer)
- Surveillance targeting a specific pathogen
- Review of infection rates after the fact
Correct answer: Monitoring of pre-diagnostic clinical indicators to detect outbreaks early
Syndromic surveillance monitors clinical syndromes and symptoms before definitive diagnoses are made, enabling earlier outbreak detection.
Question 2: A hospital implements a new central line bundle. To evaluate its impact, the IP should compare CLABSI rates:
- Only after six months of implementation
- Before and after bundle implementation using control charts (Correct answer)
- With national NHSN data only
- Using a cross-sectional prevalence survey
Correct answer: Before and after bundle implementation using control charts
Control charts allow the IP to compare pre- and post-intervention rates over time, distinguishing true improvement from random variation.
Question 3: Which NHSN event type covers infections related to implanted devices such as cardiac pacemakers?
- SSI - organ/space
- Cardiovascular system infection (VASC) (Correct answer)
- SSI - deep incisional
- Bloodstream infection (BSI)
Correct answer: Cardiovascular system infection (VASC)
NHSN's cardiovascular system infection (VASC) module covers infections related to implanted vascular devices including pacemakers.
Question 4: During outbreak investigation, the epidemic curve is primarily used to:
- Identify the causative pathogen
- Determine the mode and timing of transmission (Correct answer)
- Calculate the attack rate
- Establish the case definition
Correct answer: Determine the mode and timing of transmission
The epidemic curve's shape and timeline help identify the mode of transmission (common source vs. propagated) and approximate exposure time.
Question 5: Which of the following is a limitation of using administrative (billing/ICD) data for HAI surveillance?
- It lacks information on patient demographics
- It may not capture all clinically confirmed HAIs (Correct answer)
- It cannot be used for benchmarking
- It is not available in electronic format
Correct answer: It may not capture all clinically confirmed HAIs
Administrative data relies on coding accuracy and may miss HAIs not coded or miscoded, making it less reliable than clinical surveillance.
Question 6: The 'denominator' in a ventilator-associated event (VAE) rate per 1,000 ventilator-days represents:
- Total ICU patient-days
- The sum of all days patients were on mechanical ventilation (Correct answer)
- Number of ventilator initiation events
- Number of ICU bed-days
Correct answer: The sum of all days patients were on mechanical ventilation
Ventilator-days is the sum of each day every ventilated patient was on mechanical ventilation, reflecting the actual exposure risk.
Question 7: An infection preventionist finds that MRSA bloodstream infection rates appear higher in December than in July. Before concluding a seasonal trend exists, the IP should first:
- Immediately alert administration
- Check whether the difference is statistically significant and adjust for patient-days (Correct answer)
- Implement enhanced contact precautions in winter
- Report the finding to the state health department
Correct answer: Check whether the difference is statistically significant and adjust for patient-days
Apparent seasonal differences may reflect random variation or changes in denominator data; statistical testing is required before drawing conclusions.
CBIC Surveillance 4
Which of the following best describes 'syndromic surveillance'?