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Using an Epi Curve to Determine Mode of Spread

What an Epi Curve Can Tell You

An epi curve is a visual display of the onset of illness among cases associated with an outbreak.

You can learn a lot about an outbreak from an epi curve, such as

  • Time trend of the outbreak, that is, the distribution of cases over time
  • “Outliers,” or cases that stand apart from the overall pattern
  • General sense of the outbreak's magnitude
  • Inferences about the outbreak's pattern of spread
  • Most likely time of exposure