The geographic and temporal characteristics of the confirmed patients with human infection of avian influenza A (H7N9) virus from whom the positive clinical specimens were collected.

<p>The numbers of the enrolled patients from each location are presented individually for the DAAN assay (A), the Puruikang assay (B) and the Liferiver assay (C). The percentages of the clinical specimens that were collected during the first epidemic period (blue) and the second period (red) are illustrated by the pie charts in parts A and C of this figure. The line connecting the geographic map and the pie chart helps to identify the case number from the collection location related to the epidemic wave. The text and the following number above the line indicate the name of the collection location and the case number of each location. The dark-to-light red color on the map of mainland China indicates different levels of infection cases as of May 2014, which is interpreted in the lower left quarter of the figure.