Chapter 24 Exercises: Epidemiological Surveillance
Exercise 24.1 — John Snow Methodology Analysis
Type: Individual / Historical Analysis Difficulty: Introductory Estimated time: 30–45 minutes
Instructions:
Locate a high-quality reproduction of John Snow's original 1854 cholera map (available from UCLA's John Snow site: ph.ucla.edu/epi/snow.html or through a simple image search). Examine it carefully, then respond to the following:
Part A: Describe what information is represented in the map. What does each symbol mean? What geographic features are shown? What does the pattern of cases reveal, and what does Snow's map make visible that was not visible in the raw case list alone?
Part B: Snow's investigation involved interviewing residents of the Soho neighborhood about their water sources, health status, and household composition. Consider the privacy implications: 1. What information did Snow collect about specific households? 2. Would any of this information be considered sensitive by the standards of Snow's era? By contemporary standards? 3. Snow did not obtain formal consent from interviewees — the concept did not exist in its modern form. What ethical obligations did he have to his subjects?
Part C (150 words reflection): The chapter calls Snow's investigation "the origin story of modern epidemiology." In what sense was it surveillance? In what sense was it something different — investigation, science, or public service? Does the distinction matter?
Exercise 24.2 — NNDSS and Mandatory Reporting
Type: Individual / Research Difficulty: Intermediate Estimated time: 45–60 minutes
Instructions:
Go to the CDC's NNDSS website (cdc.gov/nndss) and the Council of State and Territorial Epidemiologists (cste.org). Find the current list of nationally notifiable conditions.
Part A: Select five conditions from the notifiable disease list that you find most interesting or surprising. For each: - Is it something you would expect to be notifiable? Why or why not? - What information is required to be reported (look for the case definition and reporting requirements)? - Who is required to report it? - What does reporting this condition involve for the patient's privacy?
Part B: Now look up your state's notifiable disease list (most state health department websites publish this). Are there conditions on your state's list that are not on the national list, or vice versa? What explains these differences?
Written analysis (300 words): The notifiable disease list is developed through a combination of public health science, political negotiation, and professional consensus. What does your research suggest about the factors that determine which conditions are reportable? Should patients have input into which conditions are designated as notifiable? Why or why not?
Exercise 24.3 — The Contact Tracing Interview
Type: Pairs / Role Play Difficulty: Introductory to Intermediate Estimated time: 30–40 minutes
Instructions:
One student plays a contact tracer; the other plays a recent COVID-19 close contact who is a college student (similar to Jordan in the chapter opening). The contact tracer should work through the following standard questions:
Contact Tracer Questions: 1. When did you last see [the positive case]? Where were you, and for approximately how long? 2. Were you wearing masks? Were you indoors or outdoors? 3. Who else was present? 4. Have you been in any other group settings in the last 10 days? (What settings, how many people, what duration?) 5. Are you a student or employee? What is your housing situation? 6. Have you had any symptoms in the last 10 days? 7. What is your current vaccination status?
The student playing the close contact should decide how much to disclose and should make at least one decision about whether to fully describe an activity (such as attending a political event, visiting a family member who is undocumented, or attending a religious service).
Post-exercise reflection (individual, 250 words): What information did the contact tracer elicit? What did the close contact decide not to fully disclose, and why? What does this exercise reveal about the gap between the public health purpose of contact tracing (disease control) and its potential secondary effects (disclosure of political activities, family situations, or other sensitive information)?
Exercise 24.4 — Biobank Ethics
Type: Small group / Case analysis Difficulty: Advanced Estimated time: 60 minutes
Instructions:
Your group has been asked to advise an IRB (Institutional Review Board) on the consent form for a new biobank at Hartwell University. The biobank will collect: - A blood sample (for DNA extraction and biochemical analysis) - Responses to a health and lifestyle questionnaire - Permission to link the sample to electronic health records from Hartwell's health center - Permission to recontact the participant for future studies
The broad consent form asks participants to agree that their samples may be used for "future research related to health, disease, and human biology" — research that cannot be specified in advance.
Work through the following questions and prepare a 500-word advisory memo:
- Is broad consent adequate, or should participants be reconsented for each specific study? What are the practical tradeoffs?
- What specific uses of the biobank samples and data should be explicitly excluded in the consent form? (Hint: consider law enforcement, immigration, insurance, employment, and commercial uses)
- How should the consent form address the re-identification risk specific to genetic data?
- What governance mechanisms should the biobank have to protect against unauthorized uses?
- The chapter notes that genetic data creates third-party exposure — your relatives are partially characterized by your genome. Should the consent form acknowledge this? Does it create any obligations to relatives who did not consent?
Exercise 24.5 — Pandemic Surveillance and Civil Liberties
Type: Written essay Difficulty: Advanced Estimated time: 75 minutes
Instructions:
Write a 700-word essay responding to the following prompt:
"The COVID-19 pandemic demonstrated that in genuine public health emergencies, the normal civil liberties constraints on surveillance must be suspended. The alternative — slower, more privacy-protective surveillance — costs lives that a more aggressive surveillance approach would have saved."
Your essay should: - State the argument's strongest version — what evidence supports it? (Use specific examples: South Korea's GPS contact tracing, wastewater surveillance, Google mobility data) - Present the strongest counterarguments — what are the risks of suspending civil liberties constraints in emergencies? - Address the "temporary emergency" problem: surveillance infrastructure built during emergencies tends to persist and expand after the emergency ends. What does this pattern suggest about the argument? - Reach a specific conclusion about what conditions, if any, would justify emergency suspension of surveillance constraints — and what safeguards should accompany such suspension
This essay asks you to engage seriously with a position you may find uncongenial. Arguments based primarily on emotional response will receive less credit than arguments that engage with the strongest version of the opposing view.