Global map of Seasonal Influenza
Seasonal risk areas: November–April (blue), April–November (red), and year-round (yellow)
Source
Boundless vets and curates high-quality, openly licensed content from around the Internet. This particular resource used the following sources:
"Influenza Seasonal Risk Areas."
http://en.wikipedia.org/wiki/File:Influenza_Seasonal_Risk_Areas.svg
Wikipedia
CC BY-SA.
