Building an insurance against modern pandemics.

The response to the first influenza pandemic of the 21st century benefited from the extensive preparation for an avian influenza pandemic and the mild nature of the 2009 A/H1N1 swine influenza virus. However, the pandemic demonstrated the limited ability to predict influenza pandemics, to anticipate levels of cross-protection, and to deliver vaccines in a timely manner, particularly to low income countries. The lessons learned from the 2009 H1N1 pandemic are of paramount importance to develop more effective preparations against future pandemics.