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Using an Epi Curve to Determine Mode of Spread

X and Y Axes

An epidemic curve, or “epi curve,” is a visual display of the onset of illness among cases associated with an outbreak. The epi curve is represented by a graph with two axes that intersect at right angles.

The horizontal x-axis is the date or time of illness onset among cases.

The vertical y-axis is the number of cases.

Each axis is divided into equally spaced intervals, although the intervals for the two axes may differ.

This graph depicts the x and y axis on a epi curve