Which of the following would most likely be shown on an epidemic curve?

• A. A graph of case onset over time
• B. A map of geographic distribution
• C. A list of vaccine brands
• D. Hospital bed occupancy chart

Answer: (A)

Epidemic curves illustrate the timing of disease onset in a population. They plot the number of new cases by time, usually days or weeks, so you can see when people started feeling ill and how the outbreak unfolds over time. This focus on onset timing is what makes the graph of case onset over time the best representation for an epidemic curve, because it directly shows how transmission and incidence change as the outbreak progresses.

Other options don’t capture the timing of cases. A geographic distribution map shows where cases occur, not when they occur. A list of vaccine brands isn’t related to how an outbreak spreads over time. A hospital bed occupancy chart reflects healthcare demand and capacity usage, not the pattern of case onset.