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Person, place, and time are the three characteristics one focuses on in descriptive epidemiology. The line listing gives us some information about person, and the epidemic curve gives us a visual sense of how the outbreak evolved over time. Given what we know about the biology and epidemiology of hepatitis A, the information suggests a point source, possibly contaminated food or an infected food handler.

The spot map below focuses on "place" by showing where each of the known cases lives. The cases are clustered somewhat more densely in the center of Sparta, but they are fairly scattered and do not suggest a specific location. So, in this case, the spot map by itself does not help pin down the source . These cases could have been exposed to a common source, such as an infected food handler, but they also could have been infected during foreign travel . For example, they might have been a group of residents from a church or school recently returned from a trip to South America.