China announced on March 31 that H7N9 avian influenza had been found in humans for the first time, and the number of confirmed cases has steadily risen since.
Here is a look at the geographical distribution of the reported cases so far.
The size of each circle represents the number of reported infections, while the colour of each circle shows the number of reported deaths.
Move the slider to see how the flu has spread day by day.
The map will be updated on a daily basis.