Creating Multi Series and MMWR Style Epi Curves

Creating Multi-Series and MMWR-Style Epi Curves

⚠️ Feature in development: This feature is in development and is not yet available on the main MicrobeTrace site.

The expanded Epi Curve View supports four related tasks:

1. Compare up to three date series as side-by-side bars.
2. Overlay case-count bars with as many as two line series.
3. Count records or sum a numeric value within each time bin.
4. Add publication-ready titles, axis labels, footnotes, legends, and dated annotations.

Before you begin

• Load a node list that contains at least one date field.
• For multiple series, the file can contain up to three date fields.
• To plot a value other than the number of records, include a numeric field for that series.
• Each value field is summed within the bins created from its corresponding date field.

The example MMWR_measles_epi_curve.csv (Right-click to save) is a synthetic daily dataset with case counts and two precomputed cumulative vaccination series. It resembles an MMWR figure but does not contain surveillance data.

Load the example data

1. Open the Files tab.
2. If MicrobeTrace displays its license agreement, review and accept it to continue.
3. Add MMWR_measles_epi_curve.csv as a node list.
4. Select ID as the node identifier.
5. Select Launch.
6. Open View > Epi Curve.
7. Select the settings button in the upper-left corner of the Epi Curve View.

Use case 1: Compare date series side by side

Use this workflow to compare two or three event-date fields as grouped bars.

1. On the Graph tab, set Graph Type to Multi: Side by Side.
2. Choose the first Date Field.
3. For Value Field 1, choose one of the following:
   • Count records counts the records in each date bin.
   • A numeric field sums that field within each date bin.
4. Repeat the date-field and value-field selections for the second and, optionally, third series.
5. Choose a color for each series.
6. Set the Bin Size to Day, Week, Month, Quarter, or Year.

MicrobeTrace displays the selected series as adjacent bars that share the same date and value axes.

Use case 2: Create an MMWR-style bar and line overlay

Use this workflow when the first series should appear as bars and the other series should appear as lines. In this mode, line values use the left Y-axis and bar values use the right Y-axis.

On the Graph tab, enter these settings for the example dataset:

Setting	Value
Graph Type	Multi: Overlay
Date Field	No. of measles cases in 2025
Bar Value	Measles case count
Date Field 2	No. of MMR doses administered in 2025
Line 1 Value	Cumulative MMR doses administered in 2025
Line 1 Style	Solid
Date Field 3	No. of MMR doses administered during the same period in 2024
Line 2 Value	Cumulative MMR doses administered during the same period in 2024
Line 2 Style	Dashed
Bin Size	Day
Epi Curve	Noncumulative

Use the color controls at the right of the date fields to distinguish the bar and line series. For an MMWR-style palette, use #9ec5e5 for the bars and #005bbb for both lines.

Keep Epi Curve set to Noncumulative when a selected value field already contains cumulative totals. Otherwise, MicrobeTrace will calculate another running total from those values.

Set the date ticks and legend

Open the Legend & Labels tab.

1. Set Tick Unit to Automatic, Day, Week, Month, or Year.
2. Set X-axis Interval to the number of selected units between labels. For example, a tick unit of Day and an interval of 14 places a label every 14 days.
3. Choose whether the legend appears on the left, top, right, or bottom, or hide it.
4. Adjust the axis-label and legend-label sizes as needed.

For the example, use Day, an interval of 14, and a Top legend.

Add titles, axis labels, and a footnote

Open the Titles & Axes tab. Blank fields use the standard Epi Curve labels.

For the example, enter:

• Chart Title: FIGURE. Number of laboratory-confirmed measles cases, by onset date, and cumulative number of measles, mumps, and rubella vaccine doses administered — New Mexico, 2024 and 2025
• X-axis Label: Onset date
• Left Y-axis Label: Cumulative no. of MMR doses
• Right Y-axis Label: No. of measles cases in 2025
• Footnote: Abbreviation: MMR = measles, mumps, and rubella.

Long titles and footnotes wrap automatically to fit the chart.

Add dated annotations

Open the Annotations tab and select Add annotation. Enter a date and an optional label for each event.

For the example, add:

Date	Label
2025-02-14	measles outbreak declared
2025-08-14	end of last patient's infectious period
2025-09-26	measles outbreak declared over

MicrobeTrace places each annotation above its date and draws a leader line to the X-axis. An annotation outside the plotted date range remains saved but is not displayed.

Review and export the chart

Close the settings window to review the finished chart.

Select the download button in the upper-left corner of the Epi Curve View to export the chart as an SVG or PNG file. The export includes the title, axes, legend, footnote, and annotations.

Choosing cumulative or noncumulative values

• Select Cumulative when MicrobeTrace should calculate a running total from per-record counts or per-bin values.
• Select Noncumulative when each bin should stand alone or the selected value field already contains a cumulative total.
• Numeric value fields are summed within each bin. Precomputed daily cumulative values generally work best with Day bins unless the dataset contains only one record per larger bin.

Quick troubleshooting

• A value field is missing: MicrobeTrace only lists fields whose populated values are numeric.
• The chart is blank: Confirm that at least one selected date field contains valid dates.
• A line is unexpectedly large: If its value field already contains running totals, select Noncumulative.
• Dates are too crowded: Increase X-axis Interval or choose a larger Tick Unit.
• An annotation is missing: Confirm that its date is within the chart's plotted date range.
• The axes seem reversed: In Multi: Overlay, lines use the left Y-axis and bars use the right Y-axis.