Fig. 1
From: Genomic surveillance of avian-origin influenza A viruses causing human disease
Cumulative numbers of H5N1 and H7N9 avian influenza virus genomes available in public databases since their first emergence dates in 1997 and 2013, respectively. Numbers of genomes (left-hand y-axis) are shown for both complete and partial genomes of a H5N1 and b H7N9. The orange line shows the cumulative number of human cases of each strain observed over the same timescale (right-hand y-axis). Selected events during the timeline of virus emergence and spread are indicated