Add to ORKGUpdated: June 16, 2010This document summarizes key events of the 2009 H1N1 pandemic and CDC\u2019s response activities for historical purposes. This document is a summary; it is not a comprehensive account of all CDC actions and activities nor is it intended to represent response efforts by other agencies and partners.Pandemic Preparedness, Background -- A Virus Emerges -- Response Ramps Up -- World Braces for Possible Pandemic -- CDC Laboratories Bolster Nation\u2019s Testing Capacity -- CDC Shares Personnel, Guidance, Early Results of Studies -- A Pandemic is Declared -- Ongoing Surveillance & Response -- 2009 H1N1 Vaccination -- A Summary of Communication Activities -- Related Links.2010Human Influenza A (H1N1), 2009830